I have been making time machine backups for years on my macbook air. Today I asked it to make one again and it came back with an error saying that the startup disk needs to be repaired. So I booted into cmd-r and repaired the disk. It fixed some problems and now that I tried running the backup again, i got the same error.
Any ideas?
MacBook Air, OS X Yosemite (10.10.1), Late 2012
The startup drive is failing, or there is some other internal hardware fault.
Make a "Genius" appointment at an Apple Store, or go to another authorized service provider.
If privacy is a concern, erase the data partition(s) with the option to write zeros* (do this only if you have at least two complete, independent backups, and you know how to restore to an empty drive from any of them.) Don’t erase the recovery partition, if present.
Keeping your confidential data secure during hardware repair
Apple also recommends that you deauthorize a device in the iTunes Store before having it serviced.
*An SSD doesn't need to be zeroed.
Ijust remembered a few days ago I tried plugging my backup drive into a Windows machine and I created a folder in it. Could that have caused this?
No.
Since haven't had time to program my genius appointment, I ran verify disk again on booting to cmd-r. I tried backup again and it ran for about 2 hours backing up a total of 80GB.
AT some point while it was doing this, I lost track and when I came back the machine had gone to sleep. I awoke and unlocked it and it was at Preparing backup but this time for a total of 40GB. It's still working on that one (10 minutes later) but at least I didn't get the backup failed error this time.
Time Machine backup fails
