Server Backup - The media is write-protected (0x80070013)

I think that most are looking at the target drive as the problem.  I think the source drive is the problem.  I migrated to a new SSD and haven't had the problem with backup's that I had before.  (0x80070013)  The media is write-protected. I ran a backup last night using Windows Backup and it was taking forever.  I looked at my drive during the backup and there was a consistent hit creating the System Image.  I stopped the backup and restarted it and it completed in about 20 min.  There was no problem reported in Event Viewer.  Not sure what the problem was.    Any thoughts?