I've been using the backup for months with no problem. I added another file share to the backup schedule and now they are all failing with "job failed because another backup job was in progress". My theory is the backup is taking too long to finish before the next one kicks in. I have them scheduled everyday at 01:00, 13:00, 18:00. About 500Gb of data total. The amount I added was about 200Gb.
Jim