Symptoms
After upgrade from POA 5.4 to 5.5 Windows File Manager is not working.
Error in CCP:
Service Unavailable
The corresponding service is not available at the moment, trying it withing 2-3 minutes.
For more information please contact your service provider.
Cause
In POA 5.5 WinFileManager is replaced by WebFileManager, and on winfm node a new site and new application pool are created in IIS:
App. Pool: WebFileManager Pool (running under identity "\wda_p00000...);
Site: WebFileManager Site (path C:\Program Files (x86)\SWsoft\PEM\sysvhosts\elFinder).
But this pool and site are absent on winfm because corresponding POA tasks have not been processed properly.
Resolution
Process all tasks with names like "WebFileManager configure...".
In case after tasks processing WebFileManager is still not functional - reinstall it on winfm node as described in guide