Synchronization Failed

[in7327]

MusicBee v3.0.6335.15398 (Win10.0), 10 Jun 2018 12:57:

System.NullReferenceException: Object reference not set to an instance of an object.
   at

[phred]

You're using an extremely old version. I suggest upgrading to at least 3.1. Better still go to 3.2. Lots of fixes and improvements have been made since the version you're using.