> 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/general/instrumentation-general-troubleshooting-list/000005382.md).

# Troubleshooting Green LED Failed polling LED status error on MiSeq

In MiSeq Control Software v4.X (Win10), some runs may present a notification message: **GreenLED: Failed polling LED status**.

The message typically does not stop the run, nor impact run performance, and is usually due to a communication issue on the instrument.

![](https://761066130-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FGM9W2DuBTgEXv1ClCm8H%2Fuploads%2Fgit-blob-03facbc87cde458112cceeadf3b132e7775ccc7e%2Fimage1.jpg?alt=media\&token=a76a01c5-21cd-46c7-8cd4-2368e4648616)

**Troubleshooting Steps**:

1. Contact [Illumina Technical Support](https://www.illumina.com/company/contact-us.html#/united-states/technical-support) for instructions on how to upload the compressed folders to a secure FTP site for review.
   1. From within D:\Illumina\MiSeq Temp\[RunFolder]\\\
      InterOp folder\
      RunInfo.xml\
      RunParameters.xml\
      Cycle Logs (found within D:\Illumina\MiSeq Temp\[RunFolder]\Logs)
   2. From within D:\Illumina\MiSeq Control Software\
      Logs folder
2. Power cycle the MiSeq **after** the run completes.
3. If the instrument initializes successfully, continue using it for sequencing and monitor the next run.
4. If the instrument fails to initialize, contact [Illumina Technical Support](https://www.illumina.com/company/contact-us.html#/united-states/technical-support).

For further information, search for Knowledge Base articles [How to Power Cycle the MiSeq](/instrumentation/miseq-ruo/instrumentation-miseq-ruo-reference_material-list/000001894.md) and [How To Power Cycle the MiSeq Video](/instrumentation/miseq-ruo/instrumentation-miseq-ruo-reference_material-list/000005871.md).

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| *For any feedback or questions regarding this article (Illumina Knowledge Article #5382), contact Illumina Technical Support* [*techsupport@illumina.com*](mailto:techsupport@illumina.com?subject=Question%2FFeedback%20Regarding%20Illumina%20Knowledge%20Article%20#000005382%20-%20Instrumentation%20\&body=Dear%20Illumina%20Technical%20Support,%0D%0A%0D%0A)*.* |


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