# Troubleshooting pre run check failure due to "Imaging test failed" on the NextSeq 1000/2000
Users may encounter the following error during pre run checks:
**Imaging test failed. The imaging metric Worst bit error rate was out of spec.**
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This error occurs during dry pre run checks, reagents have not yet been marked as used.
**To troubleshoot**:
1. Select "Retry" to re-attempt starting the run.
2. If error persists after retrying, Power Cycle the instrument and attempt to start the run again. See [How to power cycle the NextSeq 1000/2000](https://knowledge.illumina.com/instrumentation/nextseq-1000-2000/instrumentation-nextseq-1000-2000-reference_material-list/000003038#:~:text=To%20power%20cycle%20the%20instrument%3A%20From%20the%20control,side%20of%20the%20instrument%20until%20the%20lights%20fade.).
3. If error persists after power cycling instrument, collect the following files and contact Illumina Technical Support:
1. Perform **Bit Error Rate test** of System Check, results are found within /usr/local/illumina/systemcheck. See [System Checks for the NextSeq 1000/2000](https://knowledge.illumina.com/instrumentation/nextseq-1000-2000/instrumentation-nextseq-1000-2000-reference_material-list/000003457).
2. **Control Software logs** within /usr/local/illumina/logs/next1k2k-control-software
3. **Run** **set up logs** within /usr/local/illumina/runs/setup/
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| *For any feedback or questions regarding this article (Illumina Knowledge Article #9854), contact Illumina Technical Support* [*techsupport@illumina.com*](mailto:techsupport@illumina.com?subject=Question%2FFeedback%20Regarding%20Illumina%20Knowledge%20Article%20#000009854%20-%20Instrumentation%20\&body=Dear%20Illumina%20Technical%20Support,%0D%0A%0D%0A)*.* |
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