How to troubleshoot Bit Error during pre run checks on the NextSeq 500/550 and MiniSeq

A ‘Bit error check failed’ error can indicate a transient communication issue with the instrument control software (Figure 1). The error can occur when launching the instrument control software on the NextSeq 500/550 or MiniSeq or when performing the pre-run check. Usually the error can be resolved by power cycling the instrument.
Figure 1. "Bit error check failed Originally caused by: DMA Read failed with return code 32" To Power Cycle the Instrument:
  1. 1.
    From home screen, select Manage Instrument.
  2. 2.
    Select System Shutdown Options.
  3. 3.
    Select Shut Down to close the control software and turn off the instrument.
  4. 4.
    When the instrument is off, wait 3-5 minutes and turn the instrument back on by pressing the power button in the front.
  5. 5.
    Let the control software initialize.
After the power cycle is complete and the control software is initialized, repeat run setup and perform the pre-run check. If the pre-run check passes without error proceed with the sequencing run. No further action is required. If the issue persists, contact Illumina Technical Support for additional assistance. Additional Resources:
For any feedback or questions regarding this article (Illumina Knowledge Article #6684), contact Illumina Technical Support [email protected].
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