Troubleshooting Bit Error on the NextSeq 500/550 and MiniSeq

• The following error occurs when launching the Control Software or during the pre-run check of the imaging system on the NextSeq 500/550 or MiniSeq.

• This error can result from a transient communication issue or an issue with the optical system.

• Typically the error can be resolved by power cycling the instrument.

• Note: Bit rate error is resolved in instruments upgraded to NextSeq 500/550 Control Software (NCS) v4.0.1.

Error Language: Bit error check failed Originally caused by: DMA Read failed with return code 32.

Figure 1. "Bit error check failed Originally caused by: DMA Read failed with return code 32"

Troubleshooting steps:

1. Open Control Panel → Device Manager and verify Illumina DMA Driver under Data Acquisition is loaded or not.

• Illumina DMA Driver is present, power cycle the instrument once and restart the run.

• Illumina DMA Driver is NOT present, power cycle the instrument once. Login to sbsadmin and open the Control Panel → Device Manager to verify if Illumina DMA Driver under Data Acquisition is now loaded or not. If Illumina DMA Driver is present now, restart the run.

1. If Illumina DMA Driver is still not present, power cycle the instrument a second time. Login to sbsadmin, and open the Control Panel → Device Manager to check if Illumina DMA Driver under Data Acquisition is now loaded or not. Note that sometimes the second power cycle is required.

• If “Illumina DMA Driver” is present now, restart the run.

• If “Illumina DMA Driver” is still not present, contact Illumina Technical Support.

To power cycle the instrument:

1. From the home screen, select Manage Instrument.

2. Select System Shutdown Options.

3. Select Shut Down to close the control software and turn off the instrument.

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. Allow the control software initialize.

Additional resources:

• NextSeq 500 and NextSeq 550 Sequencing System Guide

• MiniSeq System Guide

• For further information, search for Knowledge Base article How to Perform a NextSeq 500/550 Power Cycle.

For any feedback or questions regarding this article (Illumina Knowledge Article #6684), contact Illumina Technical Support [e-mail].