The Resource Hosting Subsystem (Rhs.exe) process stops unexpectedly when you start a cluster resource in Windows Server 2008 R2

The path defined for the cluster resource DLL contains a system environment variable in the path, which contains another environment variable in its path. The RHS.exe process incorrectly overwrites heap memory beyond its tail when the RHS.exe process expands the multiple system environment variables.

There are no cluster resource DLL provided by Microsoft contains nested environment variables in the path to of resource DLL’s. As a result, any RHS crash with a Microsoft resource DLL will not be resolved by applying this hotfix. Please review the associated Event ID 1230 for the resource type that is being affected. Additionally review the configured path to the resource DLL to verify applying this hotfix is appropriate.

As part of normal cluster health detection, if a cluster resource does not respond to requests in a timely fashion the cluster service may attempt to recover by terminating the Resource Hosting Subsystem (RHS) process associated with the resource so that the resource can be restarted and recovered.  An Event ID 1146 under these conditions should be considered normal cluster operations.  To troubleshoot, review the resource DLL which became unresponsive and the entry point which was being attempted to be called to it.  This is most commonly IsAlive or LooksAlive health checks to resources to verify the associated service or application is healthy.