The printer’s touchscreen displays error messages if the printer encounters any abnormalities and displays more details about the error.

Configure Dashboard settings to receive SMS or email notifications for the errors listed in this article and for other print events.

Formlabs printers maintain diagnostic logs to provide detailed information about the printer. Include these diagnostic logs with other relevant observations and details when contacting Formlabs Support or your authorized reseller to speed up resolution.

For printers connected to the internet over an active Wi-Fi or Ethernet connection:

1. Tap the wrench icon on the bottom left of the printer's Home screen. The Settings screen appears.
2. Tap System. The System screen appears.
3. Tap Upload Diagnostic Info. A confirmation message to upload diagnostic information appears.
4. Tap Next to start the upload. A confirmation message appears when the upload is complete.
5. If the printer displays an error message indicating that it cannot upload the logs, there may not be enough storage space on the printer for the upload. Delete print jobs from the Queue to clear enough storage space to upload the diagnostic logs.
6. Restart the printer and try again.

For printers not connected to the internet:

1. Open PreForm.
2. Click Edit Job Setup. The Job Setup window opens.
3. Select the printer’s serial name.
4. Click Download Logs. A confirmation window appears.
5. Click Browse to download the diagnostic logs to a preferred location on your computer.
6. Click OK. The diagnostic logs save and appear in the encrypted FORMLOGS format.
7. Attach the file when contacting Formlabs Support or your authorized reseller.
8. If PreForm displays the message ERROR_BAD_STATE, there may not be enough storage space on the printer for the upload. Delete print jobs from the Queue to clear enough storage space to upload the logs.
9. Restart the printer and try again.

Learn more about options for network and non-network connections.

The printer displays Cartridge Dispense Error if it tries to dispense resin but nothing comes out of the cartridge. Usually, this means the cartridge is empty. Each cartridge contains and can reliably dispense one liter of resin. After the full liter dispenses, dispose of the cartridge and continue printing with a new cartridge.

The printer may also fail to fill the resin tank or get stuck during the filling process without displaying an error. If that happens, troubleshoot the printer as you would for a Cartridge Dispense Error. Follow the steps for resolving a Resin Level Sensor Error if the issue persists.

If a cartridge is not empty but the printer is unable to dispense resin, an issue with the cartridge may be preventing resin from dispensing:

1. Update the printer’s firmware.
2. Check that the cartridge vent cap is open.
3. Check the inside of the vent cap to ensure the vent is not blocked.
4. Consider loosening the vent cap.
5. Check the bite valve on the underside of the cartridge to make sure it opens when squeezed.
6. If the printer does not continue the print, manually pour a small amount of resin into the resin tank and try again. Remove the resin cartridge, unscrew the vent cap, pour the resin into the resin tank, replace the vent cap, and reinsert the resin cartridge. Only add a small amount of resin so as to not overfill the tank.

The printer checks the estimated amount of resin in the cartridge before starting each print. If the estimated resin supply isn’t enough to complete the part, the printer displays Cartridge Low.

Tap Ignore on the touchscreen to continue the print. However, if the printer runs out of resin in the middle of a print, it pauses until a new cartridge is inserted. Long print pauses can cause a horizontal line across printed parts. Consider swapping the low cartridge for a full cartridge before starting the print, or monitor the print closely and insert a new cartridge as soon as the current cartridge runs out of resin.

The printer displays Cartridge Error before the preprint cycle when attempting to read and write to the EEPROM chip on older, expired resin cartridges. Check the resin expiration and manufacturing dates on the sticker on the bottom of your cartridge. If the resin has expired, dispose of the cartridge and continue printing with a new cartridge. If the resin has not expired, contact Formlabs Support or your authorized reseller.

The printer displays Cartridge Incompatible if you attempt to print using custom print settings with most resin cartridges manufactured before 2021. Check the resin expiration and manufacturing dates on the sticker on the bottom of your cartridge. If the resin has expired, dispose of the cartridge and continue printing with a new cartridge. If the resin has not expired, contact Formlabs Support or your authorized reseller.

If the resin tank is overfilled, the printer will show this error. Use a syringe or small disposable cup to remove small amounts of resin, and pour it into a separate container. If the printer incorrectly warns of a resin tank overfill, check that the float can move freely and inspect the LevelSense board for damage.

If the printer does not detect an inserted tank or cartridge, check the ID chip on the resin tank or cartridge to ensure the chip is present and clean. A dirty or missing chip can prevent the printer from detecting the tank or cartridge.

Fully remove and reinsert the resin tank or cartridge. The top of an inserted cartridge should be flush with the rear of the printer. A fully-inserted resin tank locks into the tank carrier rails and will be flush against the back of the printer.

The printer checks the resin type in the tank and cartridge to ensure they match the current print job. If they do not match the resin type identified in the print job, the printer displays Resin Tank and Cartridge Warning and prompts you to insert a tank and cartridge that match the print job settings.

If the resin cartridge is inserted first, the printer displays Resin Tank Warning when the type of resin in the tank does not match the cartridge. Remove the resin tank and replace it with one that matches the inserted resin cartridge.

If the resin tank is unused and clean but has been programmed with the incorrect resin type, tap Ignore to reprogram the tank's resin type.

If the resin tank is inserted first, the printer displays Cartridge Warning when the type of resin in the cartridge does not match the tank. Remove the cartridge and replace it with the type of resin that matches the tank.

Sensors track the printer's motor movements. If a motor does not return to its original position in the right amount of time, the printer displays Motors Jammed or MOTOR_MOVE_OUT_OF_BOUNDS.

Anything in the path of a moving part may prevent the motor from moving properly. Open the cover to inspect the build platform and Light Processing Unit (LPU). Look inside the printer cavity and remove obstructions along the rails that are located at the rear of the printer cavity, paying special attention to the limit switch on the left side of the rail. Remove and reinsert the build platform and resin tank.

The printer stops heating if it cannot reach the target temperature of 30 °C (86 °F) after 60 minutes. In a cold operating environment, the printer may require more than one heating cycle to reach the desired temperature. Restart the print to begin heating again. For more information, refer to the support article Maintaining resin temperature.

Formlabs LFS printers use a force sensor on the Z-axis to determine when each layer has peeled off the resin tank film. If that force sensor is not responding properly, the printer peels each layer more slowly to prevent damage to the resin tank or print. As of Form 3 generation firmware version 1.13.3 and Form 3L generation firmware version 1.6.3, the printer displays Force Sensor Timeout to notify you if the force sensor is unresponsive. This message does not stop the print. To resolve this issue:

1. Update the printer’s firmware.
2. If Force Sensor Timeout messages persist, check and reseat the force sensor cable. Follow the instructions in the guide Reseating the Z-axis force sensor cable (Form 3) [EN].

Tensioner errors occur when the printer is unable to move the resin tank tensioner system. The printer UI may show one of the following error messages when this issue occurs:

• Error 147
• Error 148
• PR_ERROR_TENSIONER_TANK_NOT_TENSIONED
• PR_ERROR_TENSIONER_RELEASE_TANK_TIMEOUT
• TENSIONER_ERROR
• Tank Tensioner Failed

To resolve a tensioner error:

1. Try another resin tank, if any are available.
2. Restart the printer.
3. Update your printer’s firmware.
4. Reseat the tensioner motor cable following the instructions in the guide Reseating the tensioner motor cable (Form 3) [EN] [DE] [ES] [FR] [IT] [JA] [ZH].

If you see this error message repeatedly, contact Formlabs Support or your authorized reseller.

Error 1 is a general error message that can have multiple causes. If you encounter this error:

1. Power cycle the printer.
2. Update PreForm and your printer’s firmware.
3. Perform a factory reset on your printer.
4. Reupload and retry the print.
5. Try another resin tank, particularly if the one previously in use was past its maximum lifetime.

If the error persists, upload your printer’s logs and contact Formlabs Support or your authorized reseller for further assistance.

Every print job is uploaded to the printer from PreForm. If the printer is unable to read the file, the touchscreen displays Error 61. This error is usually caused by incompatible PreForm and printer firmware versions. It is also possible that the file was corrupted due to a poor wireless connection while it uploaded from PreForm.

If the printer displays Error 61:

1. Update the printer’s firmware and PreForm to the latest versions.
2. Adjust the print job in PreForm. Rotate or shift the model and regenerate supports to create a new print file.
3. Send the new print job to the printer via USB if possible.
4. Try to rerun the print job. If you see the same error, continue with the troubleshooting steps below.
5. Upload diagnostic logs.
6. Perform a factory reset.
7. Run the LPU replacement routine without replacing or removing the LPU to fix potential calibration issues.
   1. Tap the gear icon on the printer’s touchscreen. The Settings screen appears.
   2. Tap Maintenance > LPU Replacement. The LPU moves from its storage position to the right side of the printer into its maintenance position.
   3. When prompted by the touchscreen, disconnect the power cable before continuing.
   4. Reconnect the power cable. The printer initializes, moves the LPU back to its home position, and calibrates the LPU.

If the issue persists, contact Formlabs Support or your authorized reseller for further assistance.

These errors are caused by the printer being unable to communicate with the LPU.

1. Upload diagnostic logs.
2. Perform a factory reset.
3. If the errors continue, contact Formlabs Support or your authorized reseller for further assistance.

The LevelSense board monitors the amount of resin in the resin tank based on the height of the liquid resin. Printer firmware updates sometimes include updates to firmware for specific components, such as the LevelSense board. Error 131 relates to issues with reprogramming the LevelSense board. This issue can usually be resolved by updating your printer’s firmware to the latest version.

If you see this error message repeatedly, contact Formlabs Support or your authorized reseller.

Error 137 and Error 147 indicate a problem moving the tensioner. The tensioner pulls the resin tank film taut, but it also needs to move to allow the LPU to enter or exit its garage. Form 3 generation printers throw this error when the printer commands the tensioner to move but does not register any movement after several seconds. Similarly, Error 148 occurs when the printer tries to release the tension on the resin tank but does not get confirmation from the tensioner sensor that the tension was released. When one of these errors occurs, you may also see a Tank Tensioner Failed message displayed on the screen.

These errors could be caused by:

• Incorrectly installed tensioner leading to wear in the assembly that prevents tensioner movement
• Broken tensioner motor
• Disconnected tensioner motor
• Disconnected tensioner sensor
• Damaged resin tank

To resolve this issue:

1. Run a print with at least one other resin tank, if any are available.
2. Update your printer to the newest firmware.
3. If the errors continue, contact Formlabs Support or your authorized reseller for further assistance. Provide a video of the tensioner activity during preprint or printer startup.

At the start of each print, the LPU housing pulls the tank mixer back and forth across the tank film several times. This motion mixes the resin in the tank while also checking for cured resin on the film and on the build platform. If the mixer encounters cured resin blocking its path, its magnets decouple from the magnets in the LPU housing and the printer pauses the print. This is the designed behavior of the mixer and is intended to protect the tank film and prevent further print failures.

The printer will display a Mixer Check Failure message if:

• the mixer gets stuck on anything
• the printer loses track of the mixer
• the printer detects that the mixer is moving oddly

The printer will display Error 169 if:

• the mixer coupler was unable to flip upwards
• the sensor that detects mixer coupler movement is damaged or malfunctioning

See the section Mixer Check Failure for troubleshooting information.

During a print, Formlabs LFS printers tension the flexible film at the bottom of the resin tank to create a flat, even surface for printing. This stretches the film over time. To account for this, the printer applies tension slowly until the slack in the film is removed before pulling with a specified target force. If this tensioning the film, the printer displays Error 186 or PR_ERROR_TENSIONER_FAIL_TO_SLACKOUT. This may mean that the resin tank is old and the tank film has reached the maximum allowable amount of stretch, or that the tensioner has malfunctioned. To resolve this issue:

1. Update your printer’s firmware.
2. Retry your print with another resin tank, if one is available. If the replacement tank works, your original tank’s flexible film has reached the maximum allowable amount of stretch and should be disposed of. In most cases, resin tanks become unusable due to damage or reach their maximum lifetime before the tank film stretches this much.

If the issue persists, upload your printer’s diagnostic logs, then contact Formlabs Support or your authorized reseller for further assistance.

On Form 3 generation printers, Error 200 or PR_ERROR_AUTOSCALE indicates that a component within the Light Processing Unit (LPU) has tripped the printer’s internal electrical fuse. The error is uncommon and sometimes resolves itself. To resolve this error:

Error 246 or PR_ERROR_WHIPPET_ERROR_FUSE indicates a communication issue between the printer and the LPU. This could be due to an improper command to the galvanometer in the LPU, a power issue, incorrect LPU calibration, or a software bug. To resolve this issue:

1. Upload diagnostic logs.
2. Perform a factory reset.
3. Update the printer’s firmware and PreForm to the latest versions.
4. Check the flex cable that connects to the Light Processing Unit (LPU) for damage.
   1. Tap the gear icon on the printer’s touchscreen. The Settings screen appears.
   2. Tap Maintenance > Motor Moves. Hold Left until the LPU housing reaches the middle of the printer cavity.
   3. Disconnect the printer from power, open the cover, and inspect the ribbon cable visible on the right side of the LPU housing.
   4. If the LPU ribbon cable is damaged, it may need to be replaced. The cable is available on the Formlabs Store. Contact Formlabs Support for additional assistance.
   5. After inspecting the ribbon cable, close the cover and reconnect the printer to its power source.
5. Run the LPU replacement routine without replacing or removing the LPU. This routine is done only to fix calibration issues. Follow the steps below:
   1. Tap the gear icon on the printer’s touchscreen. The Settings screen appears.
   2. Tap Maintenance > LPU Replacement. The LPU housing moves from its storage position to the right side of the printer into its maintenance position.
   3. When prompted by the touchscreen, disconnect the power cable before continuing.
   4. Reconnect the power cable. The printer initializes, moves the LPU housing back to its home position, and calibrates the LPU.

If the issue persists, you may need to replace the LPU. Replacement LPUs are available on the Formlabs Store. Contact Formlabs Support for additional assistance.

If the printer restarts unexpectedly while in the middle of a print job, it will show Error 293 when it turns back on. This is a generic error that displays when the printer does not finish a print job normally. This error is usually caused by a power outage or a loose power cable. If the problem persists after trying another outlet, contact Formlabs Support or your authorized reseller. If your area has frequent power outages or brownouts, consider purchasing and plugging your printer into an uninterruptible power supply (UPS).

Error 310 and Error 311 indicate that the printer encountered an issue while running the Z-axis calibration procedure. The intent of the calibration is to measure the exact pitch of the build platform in relation to the LPU housing, so the printer can compensate for any tilt during the first few layers or a print. The printer lowers the build platform repeatedly as it moves the LPU housing across the build platform. With each move, it measures how far down the build platform has to travel to make contact with the roller holder. The printer displays an error if the left and right sides of the build platform have travel distances that differ by at least 0.4 mm. This can be due to:

• Resin cured on the build platform or underneath the print surface (e.g., on the Build Platform 2 or Build Platform 2L)
• A slight tilt in the angle of the build platform
• A slight tilt in the angle of the LPU housing or roller holder

To resolve this issue:

1. Make sure your build platform is completely clean. If you are using a Build Platform 2 or Build Platform 2L, remove the print surface and clean both the underside of the print surface and the body of the build platform. When reassembling the build platform, make sure that the print surface is correctly seated.
2. After cleaning, run the calibration again.
3. Try a different build platform, if one is available.

If the calibration continues to fail, contact Formlabs Support or your authorized reseller for further assistance.

Error 345 indicates that the print couldn't start because of an unexpected error. To resolve this issue:

1. Perform a factory reset on your printer.
2. Reupload and retry the print.

If the error persists, upload your printer’s logs and contact Formlabs Support or your authorized reseller for further assistance.

Each cartridge contains and can reliably dispense one liter of resin. After the full liter dispenses, dispose of the cartridge and continue printing with a new cartridge. Restart the print once the depleted cartridge has been replaced.

The LevelSense board is located directly behind the resin tank. It senses the position of a metal float in the resin tank to determine the amount of resin in the resin tank. The printer may display Resin Level Sensor Error if there is an issue with the float or the LevelSense board.

If the printer displays Resin Level Sensor Error, follow each step to see if that step resolves the error:

1. Ensure that the printer is level.
2. Inspect the resin tank:
   • Remove the resin tank.
   • Check that the float can move freely.
   • Reinsert and push the tank all the way back. The touchscreen displays a confirmation message when the resin tank is properly seated.
3. Inspect the LevelSense board:
   • Remove the resin tank.
   • Inspect the LevelSense board. Contact Formlabs Support or your authorized reseller if you see damage.
4. Recalibrate the LevelSense board:
   • Tap the wrench icon on the printer’s touchscreen. The Settings screen appears.
   • Tap Maintenance. The Maintenance screen appears.
   • Tap Calibration > Resin Level Calibration.
   • Follow the on-screen instructions:
     • Tap Next to start the calibration process.
     • Remove the resin tank from the printer (if one is inserted) and tap Next.
     • Close the printer cover and tap Calibrate.
     • Once the calibration process is complete, tap Done.
5. If the printer still displays the error, try a different resin tank. If the error does not occur with a different tank, the problem may be with the resin tank.
6. If the error happens with all resin tanks, contact Formlabs Support or your authorized reseller.

When running the LevelSense calibration routine, the printer may display Calibration Error if the printer cannot reach the required temperature.

If the touchscreen displays Calibration Error, follow these steps:

1. Check that the printer’s environment is between 64–82 °F (18–28 °C) and that it is not near a cold air vent or a cold garage, etc.
2. Upload your printer’s diagnostic logs and contact Formlabs Support or your authorized reseller.

At the start of each print, the LPU housing pulls the tank mixer back and forth across the tank film several times. This motion mixes the resin in the tank while also checking for cured resin on the film and on the build platform. If the mixer encounters cured resin blocking its path, its magnets decouple from the magnets in the LPU housing and the printer pauses the print. This is the designed behavior of the mixer and is intended to protect the tank film and prevent further print failures.

The printer will display a Mixer Check Failure message if:

• the mixer gets stuck on anything
• the printer loses track of the mixer
• the printer detects that the mixer is moving oddly

The printer will display Error 169 if:

• the mixer coupler was unable to flip upwards
• the sensor that detects mixer coupler movement is damaged or malfunctioning

If the printer displays Mixer Check Failure or Error 169, follow these steps:

1. Update the printer’s firmware.
2. Remove the build platform and inspect it for cured resin or other debris.
3. Try a different mixer or resin tank, if one is available.
4. If the resin tank is new and unused, carefully pour a small amount of resin from the resin cartridge into the resin tank to coat the flexible film on the bottom. Proceed to Step 8.
5. Remove the resin tank and place it in its case.
6. Restart the printer.
7. Using the tank tool, inspect the resin tank film for cured resin or other debris.
   1. If you find any cured resin, remove it using the tank tool.

8. Reinsert the resin tank and build platform.
9. On the printer touchscreen, tap Settings > Maintenance > Calibration > Calibrate Tank Mixer Sensor and follow the instructions on the touchscreen.
   1. On screen 2 of 8, remove the mixer from the resin tank before tapping Calibrate.
   2. On screen 4 of 8, place the mixer back into the tank in the correct orientation, with the mixer’s arms facing left and the magnets facing down, before sliding the mixer all the way to the left until it clicks into place.
   3. On screen 6 of 8, make sure the mixer has moved to the middle of the tank with no decoupling. 

10. Restart the print.
11. If the printer continues to display the Mixer Check Failure error message, check the mixer coupler for obstructions by following the steps in Inspecting the Form 3 mixer coupler [EN] [DE] [ES] [FR] [IT] [JA] [ZH].
12. If the printer continues to display Error 169, you may need to replace the mixer coupler motor. Contact Formlabs Support or your authorized reseller.

Formlabs SLA printers operate best when perfectly level. The touchscreen prompts you to level the printer when necessary. Tap Settings > Printer Leveling on the touchscreen to view the current level status.

Follow the touchscreen prompts and use the leveling tool to level the printer.

If power to the printer is interrupted during a print job, the printer does not resume the print job when it restarts. The touchscreen displays Reset While Printing. If the reset was unexpected, contact Formlabs Support or your authorized reseller.

The Failed to start print error message appears if the printer is unable to determine why the print failed to start properly. In some cases, it can indicate damage to the motherboard that prevents proper connection to the laser controller or motors. To resolve this issue:

1. Power cycle the printer.
2. Update PreForm and your printer’s firmware.
3. Perform a factory reset on your printer.
4. Delete the FORM file from your computer and delete the print job from the printer.
5. Remake the print job, reupload it to the printer, and retry the print.
6. Check your printer’s connection to the computer. Reupload the print job via another connection method, if possible.
7. Try another resin tank, particularly if the one previously in use was past its maximum lifetime.

If you see this error message repeatedly, contact Formlabs Support or your authorized reseller.

The printer displays specific error messages depending on the Wi-Fi access point's response to the connection attempt. Refer to the support article Connecting to your printer to set up a connection via Wi-Fi, USB, or Ethernet. Always check with a network administrator to ensure that the wireless network is configured to allow the printer to connect. For a Windows operating system, follow Apple's instructions to ensure that Bonjour is properly installed. This step is required to connect. PreForm must be connected to the same network as the printer for wireless uploading.

Invalid network key

The password was not entered correctly. Check the network password. Check with a network administrator to ensure that the wireless network is configured to allow the printer to connect.

Connection failed

The printer failed to configure the wireless connection and could not connect to the network. Check with a network administrator to ensure that the wireless network is configured to allow the printer to connect.

The printer can display the message An unknown error has occurred in response to a variety of issues. If you see this error repeatedly, upload diagnostic logs and contact Formlabs Support or your authorized reseller.

During troubleshooting, Formlabs Support may need additional information from or access to your printer. You may be asked to enable Remote Assistance and Dashboard Logging on your machine.

To prepare your printer for remote assistance:

1. Tap the gear icon to access the Settings screen. The Settings screen appears.
2. Tap System. The System screen appears.
3. Tap Remote Assistance. The toggle turns blue when it is enabled.

To prepare your printer for dashboard logging:

1. Tap the gear icon to access the Settings screen. The Settings screen appears.
2. Tap Connectivity. The Connectivity screen appears.
3. Tap Dashboard Logging. The toggle turns blue when it is enabled.

On some occasions, a factory reset may correct unusual printer behavior. Unusual behavior may include Unknown Error messages, incomplete firmware updates, an unresponsive touchscreen, or trouble connecting to PreForm. A factory reset erases custom settings, including prints saved in the Queue and network connections.

To perform a factory reset:

To confirm a successful factory reset, tap Queue on the touchscreen. After a successful reset, the print queue is empty. If the reset does not resolve the behavior, contact Formlabs Support or your authorized reseller.