Client refuses to backup

One computer refuses to backup to the server. It started with a previous version, when updating to the latest it was able to backup once, but then stopped again.

This is the debug.log:

2018-12-20 23:12:51: Loaded -fileserv- plugin
2018-12-20 23:12:51: Loaded -fsimageplugin- plugin
2018-12-20 23:12:51: Loaded -cryptoplugin- plugin
2018-12-20 23:12:51: SQLite: recovered 2004 frames from WAL file C:\Program Files\UrBackup\urbackup\backup_client.db-wal code: 283
2018-12-20 23:12:51: urbackupserver: Server started up successfully!
2018-12-20 23:12:51: Started UrBackupClient Backend...
2018-12-20 23:12:51: FileSrv: Servername: -pc-
2018-12-20 23:12:51: Found no EFI System Partition
2018-12-20 23:12:52: Looking for old Sessions... 0 sessions
2018-12-20 23:12:52: Final path: D:\

I tried completely reinstalling the client, with and without deleting the urbackup directory. I also tried to delete the client account from the server, create a new account and download the client software from the server, but the result is the same.

Any help would be appreciated.

This is recovery from:

Since it’s a single PC problem have you checked that there aren’t system issues? Disk SMART/chkdsk?

No OS listed, why is D: in the log?

Incomplete information when asking for help