Want to share a problem I discovered with one of our Unity servers. This server was unfortunately built with too small a C drive partition. This will be corrected when I rebuild the server for Unity 5.x. As a result, I am always cognizant of the C drive filling up and have taken measures to move specific files from this drive to another location. I went to run the GUSI on this server the other day and it hung, the program went idle ... non-responsive. I just figured it out this morning :-) I moved the EngineeringSpecialBackup folder back to its default location on c:\commserver and the GUSI ran fine.