How to resolve 'An unknown error has occurred' critical system errors on the NovaSeq X/X Plus

NovaSeq X Series Control Software initialization issues that do not fit within the Control Software error reporting structure will present with the following error message:

"Critical system error - An unknown error has occurred. The system may require a restart."

If this error presents during instrument or Control Software initialization, see the following recommendations:

Troubleshooting Actions

1. Do not select Shutdown or power cycle the instrument. Instead, select Exit Application to close the NovaSeq X Series Control Software.

2. Collect the Control Software Logs from the /usr/local/illumina/logs/novaseq-x-series-control-software directory on the instrument.

3. Contact Illumina Tech Support for next steps.

For any feedback or questions regarding this article (Illumina Knowledge Article #7997), contact Illumina Technical Support [e-mail].