Time machine issues

I am having problems with time machine failing I have a external HD that TM was backing up to, but recently it says there is not enough room for the most recent back up. when i go into TM it only goes back one day. I thought it would automatically delete older back ups to keep things fresh. My HD on the mac is 250 gig and I am only using 99 gig. the external is a 160 gig. I can't figure out what is going on.

Any ideas? can i somehow reformat the external and start again.

Jon

That is a little strange.
Time machine is designed so that the first backup backs absolutely everything up, so that would be in your case 99gb. Then every hour (by default) backup any changes made.

You can re-format your external drive to see if the problem goes away. To do this you need to startup disk utility, either through spotlight or by going to Applications > Utilities > Disk Utility.

Hope this helps
- Simon

You're try to backup 99 GB worth of data onto a 160 GB drive and that's not counting the overhead....? If you've selected to backup everything (in other words, nothing excluded) that means you'll only fit one complete backup on that 160 GB drive. You need a larger external drive. I would estimate at the least, a drive of around 500 GB or larger.

Buy a new external drive - one large enough - and start the backups over again. Keep the one you already have on the 160 GB drive or erase it and start over on that drive for an updated backup.