Troubleshooting a Flow Cell Door error on the NextSeq 500/550

The following error can appear during initialization or when setting up a sequencing run or wash. This can be a communication error, especially if the instrument had not been power cycled in a while.

Error message: "Exception generated from IxCmdIllumina.Spark.EmbeddedCommandSet.ix_dlowcell_door_open : An error has occurred while executing command Originally caused by: An error has occurred while executing the command"

Troubleshooting steps:

1. Power cycle the NextSeq 500/550.

2. If instrument initializes without errors, the door can be tested as follows:

   1. Navigate to Manage Instrument and select Unload Consumables.

   2. Proceed with the wash setup.

• If the error does not re-appear, the instrument is cleared for continued use.

• If the error is recurring, contact Illumina Technical Support.

For any feedback or questions regarding this article (Illumina Knowledge Article #3265), contact Illumina Technical Support [e-mail].