WDM errors after 4.9 upgrade

WDM 4.85 Workgroup on W2K8 R2 SP1 server.
Upgraded to 4.9.

When opening WDM now, the error Application Function, GetEnvInfo: 48 File not found: RptSrvComm.dll.

Click okay and a warning that ThreadX service is not running.

Click okay to that and get another error, Application Function ErrTrap_PostConnectActions: 48 File not found: RptSrvComm.dll

Console opens but clients cannot be managed.

Cannot run installer/uninstaller again, as it results in error, Setup was unable to intialize the required libraries.

Kind of remember that the same kind of thing happened when upgrading to 4.85 previously, but can't find info on how it was fixed. Any help appreciated.

TIA
Rick