> For the complete documentation index, see [llms.txt](https://knowledge.illumina.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://knowledge.illumina.com/instrumentation/nextseq-500-550/instrumentation-nextseq-500-550-troubleshooting-list/000002053.md).

# Troubleshooting a Flow Cell Registration Failed (Skew) warning on the NextSeq 500/550

The following error message can occur during pre-run checks and is caused by a software communication issue and generally does not impact run performance.

The error states "Flow Cell Registration Failed (skew). No action necessary", as shown below.

![](/files/LYJ2pbhHfNXDZINDXx8h)

**Troubleshooting steps:**

* Monitor run until completion and review run specifications.
  * If run does not meet specifications, contact [Illumina Technical Support](https://www.illumina.com/company/contact-us.html#/united-states/technical-support).
* Power cycle instrument before next run.

For further information, search for Knowledge Base articles **Specifications for the NextSeq 500/550** and **How to Perform a NextSeq 500/550 Power Cycle.**

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| *For any feedback or questions regarding this article (Illumina Knowledge Article #2053), contact Illumina Technical Support* [*techsupport@illumina.com*](mailto:techsupport@illumina.com?subject=Question%2FFeedback%20Regarding%20Illumina%20Knowledge%20Article%20#000002053%20-%20Instrumentation%20\&body=Dear%20Illumina%20Technical%20Support,%0D%0A%0D%0A)*.* |


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