Just when you think it's safe to stop checking up on it . . . This is the second or third time Time Machine has decided to stop backing up, and keep it a secret. My setup for Time Machine is pretty straightforward, a dedicated internal 500gb backing up a single 320gb with about 180gb on it. The issue is Time Machine will stop backing up when the disk gets full, but not every time the disk gets full. The last time I did a complete do-over with T.M. , I checked it every day for a month, then every 3-5 days for a month. Periodically the disk would fill up and truncate the older backups, you would see the "Oldest Backup" date creep forward. Then I stopped checking, until yesterday when I found it stopped backing up almost two weeks ago. This has happened before. What is really upsetting is that there was absolutely no indication that there was a problem, no "failed" in the T.M. window, no '!' in the icon, nothing. This time I opened the window and watched it. "Latest Backup": 12/29/09, "Oldest Backup": 12/11/09, and we're going to do it again in an hour. If you didn't open the window you would never know anything was wrong. Available space was almost zero (2mb) and would drop a 100k once in a while. It will be "calculating changes" for a while, stop, try it again in an hour. This machine does have a VM with 80gb as part of the backup which I know is a lot to digest, but this is nothing new. The latest file in the backup is an .inProgress, dated 12/29 and would appear to be holding he entire contents (180gb). It's Date Modified time is current. I would like to keep using it because it's drop-dead easy so I want to see if I'm doing something wrong. I realize T.M. is not a Retrospect-class backup system but shouldn't it work better than this? Or, at least tell you when it's not working? Thanks for any advice.