# 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."
**Troubleshooting options available:**
1. The Universal Copy Service (UCS) error can be transient; power cycle the instrument.
* For more information, search for Knowledge Base article **How to Perform a NextSeq 500/550 Power Cycle**.
2. If the Windows password was updated recently, update the sbsuser credentials for UCS and Local Run Manager (LRM) Services.
* For information on updating credentials, search for Knowledge Base article **Updating Windows 10 credentials in NCS v4.0.1.+, MNCS v2+, MCS v4+**
3. If there was no change in credentials, move old .json files with the following steps.
* Close NextSeq Control Software (NCS).
* Stop Universal Copy Service.
* Open task manager > Navigate to Services > Locate Universal Copy Service > Right click > Select **Stop**.\
\- **Note**: The task manager may need to be launched as administrator.
* Navigate to C:\ProgramData\\\*\Illumina\UniversalCopyService\Runs (Program data may be hidden) and check to see if there are any old files (eg, .json) present.
* If old files are present in the run folder, create a folder called 'ArchivedRuns' and transfer all the files to this folder, so the runs folder is clear.
* Re-start Universal Copy Service.
* Open task manager > Navigate to Services > Locate Universal Copy Service > Right click > Select **Start**.
* 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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