If you are getting events 1558 and 1069 stating “The cluster service detected a problem with the witness resource” every 15 minutes, there is now an official fix from Microsoft. I noticed an issue like this at a previous client who had a 6 node Exchange 2010 fail over cluster with 1 file share witness.
Log Name: System
Source: Microsoft-Windows-FailoverClustering
Event ID: 1069
Task Category: Resource Control Manager
Level: Error
User: SYSTEM
Computer: node01.ali-lab.com
Description: Cluster resource ‘File Share Witness (\\node02.ali-lab.com\DAG.ali-lab.com)’ in clustered service or application ‘Cluster Group’ failed.
Log Name: System
Source: Microsoft-Windows-FailoverClustering
Event ID: 1558
Task Category: Quorum Manager
Level: Warning
User: SYSTEM
Computer: node02.ali-lab.com
Description: The cluster service detected a problem with the witness resource. The witness resource will be failed over to another node within the cluster in an attempt to reestablish access to cluster configuration data.
Solution
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You can install this fix.