> 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/000002770.md).

# Troubleshooting Universal Copy Server error on the NextSeq 500/550 (NCS 4.0+)

The following message can appear when initializing NextSeq Control Software (NCS):

"The following required software is either not installed or not running. Sequencing cannot be performed until this problem is fixed. Contact Technical Support. Universal Copy Service."

![](/files/svgTKmOFPRgM2woWTg26)

**Troubleshooting options available:**

1. The Universal Copy Service (UCS) error can be transient. First **power cycle** the instrument and attempt to restart NCS.
   1. For more information, see Knowledge Base article [How to Power Cycle the NextSeq 500/550](https://knowledge.illumina.com/instrumentation/nextseq-500-550/instrumentation-nextseq-500-550-reference_material-list/000001972).
2. If the Windows OS account password (usually SbsUser) was updated recently, and the UCS and Local Run Manager (LRM) Services log-on credentials are using the same account, these service credentials must also be updated to the new password of that OS account.
   1. For information on updating service credentials, see Knowledge Base article [How to update Windows 10 account credentials on Benchtop Instruments](https://knowledge.illumina.com/instrumentation/general/instrumentation-general-reference_material-list/000001932)
3. If there was no change in OS account credentials, **Remove** old UCS \*.json run files with the following steps.
   1. Ensure there are no runs or LRM analysis still in progress. System must be idle.
   2. Close NextSeq Control Software (NCS).
   3. Stop Universal Copy Service.
      1. Open **Task Manager** > Click the **Services** tab > Locate **Universal Copy Service**, right-click and Select **Stop**.
      2. **Note**: **Task Manager** may need to be launched as administrator.
      3. **Navigate** to C:\ProgramData\*\Illumina\UniversalCopyService\Runs
      4. **Note**: ProgramData folder may be hidden. In **Windows Explorer** click the "**View**" button and click "**Show Hidden Items**"
      5. **Check** to see if there are any old run \*.json files present.
      6. If old files are present in the run folder, **create** a folder called '\_ArchivedRuns' and **transfer** all the \*.json *and \**.log files to this folder, so the runs folder is clear.
      7. **Restart** Universal Copy Service.
      8. Open **Task Manager** > Click the **Services** tab > Locate **Universal Copy Service**, right-click and Select **Start**.
      9. Restart NCS.
4. If the above options do not resolve the error, contact [Illumina Technical Support](https://www.illumina.com/company/contact-us.html#/united-states/technical-support) for further assistance.

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| *For any feedback or questions regarding this article (Illumina Knowledge Article #2770), contact Illumina Technical Support* [*techsupport@illumina.com*](mailto:techsupport@illumina.com?subject=Question%2FFeedback%20Regarding%20Illumina%20Knowledge%20Article%20#000002770%20-%20Instrumentation%20\&body=Dear%20Illumina%20Technical%20Support,%0D%0A%0D%0A)*.* |


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