It seems that the client at some point just simply stops responding to requests. If make an args.txt change and then restart the UrBackupClientBackend service, I can force an image backup to be taken. At some point though, the service stops responding to requests and just failes with the below errors:
This doesn’t seem to be isolated to any one client either. I’ve tried making args.txt changes and restarting the client service on several Windows 7 clients and a Windows 8.1 client. All are able to take an initial image when directed from the server console, but subsequent scheduled incremental or full image backups fail.