ListUnreferencedFiles - when I run WINDU Task I got below error,

[KS_9212978]

ListUnreferencedFiles:

Diagnostic task computes the storage space occupied by unreferenced files in the system. To remove these unreferenced files from the system, follow the instructions provided in the "Maintaining Your Vaults" section of the Windchill System Administrator's Guide.

can you guide me step by step on how to remove un referenced files 

Tue 6/27/23 18:55:35: at java.lang.Thread.run(Thread.java:745)
Tue 6/27/23 18:55:35: Task failed.
Tue 6/27/23 18:55:35: com.ptc.windchill.upgrade.updates.UpdateExecutionException: Error executing IncrementalUpdate Unreferenced Files Report (#ListUnreferencedFiles)
Tue 6/27/23 18:55:35: Nested exception is: (com.ptc.windchill.upgrade.updates.directives.directivesResource/39) com.ptc.windchill.upgrade.updates.DirectiveExecutionException: Method server code wt.fv.ListUnreferencedFilesDT.executeDiagnosticTask failed. See nested exception for details
Tue 6/27/23 18:55:35: Nested exception is: (wt.pom.pomResource/10) wt.pom.PersistenceException: A commit cannot be done when a rollback is in progress. The following is the rollback stacktrace.
Tue 6/27/23 18:55:35: ROLLBACK: java.lang.Thread.getStackTrace(Thread.java:1589)

[Marco_Tosin]

Many of the user questions are matched by PTC support articles with possible answers.

You can start from here https://www.ptc.com/en/support/search

And this is the answer 

[Knowledge hub] About "Remove Unreferenced Files" in Windchill PLM

[HelesicPetr]

@Marco_Tosin 

Your link is blocked by my browser I don't know why 😄 

Link to the article CS294987

PetrH

[Marco_Tosin · Accepted solution]

Below text taken from article

Article - CS294987

[Knowledge hub] About "Remove Unreferenced Files" in Windchill

Applies To

• Windchill PDMLink 10.2 to 12.0

Description

• Knowledge summary about Remove Unreferenced Files (RUF) utility
  • What is the function of Remove Unreferenced Files utility
  • How to safely use Remove Unreferenced Files utility

Resolution

Note:

• Suggest running Remove Unreferenced Files only when absolutely necessary. i.e.  running out of disk space
  • Any mistakes of RUF will lead to data corruption seriously,
    • e.g. by mistake pointing QA/Test Windchill server to production File Server; QA system shares same physical vault folder as production system
  • If any functionality problems which need resolve via Remove Unreferenced Files, need identify the root cause from function point.
• Also strongly suggest taking option of Move files instead of deleting

Information:

• How does 'Remove Unreferenced Files' function work in Windchill PDMLink
• How to remove unreferenced files from vaults in Windchill
• How to automate "Remove Unreferenced Files" in Windchill PDMLink
  • Apply to Replica Vault only

Known problem:

• Files that are actually referenced will get deleted when "Remove unreferenced files" and "Automated cleanup of replica vaults" are running at the same time in Windchill
  • Corrected in Windchill 10.2 M020-CPS21, 10.2 M030-CPS18, 11.0 F000-CPS07, 11.0 M010-CPS02