Your signature says 10.7.5. That is the problem.
Either revert to 10.7.4 using TM
or temporarily stop Spotlight to do a TM backup
or Upgrade to Mountain Lion
See the many many posts lower down the forum for how-to's. Apple may apologise one day.
Currently Being ModeratedOct 3, 2012 12:27 PM (in response to peter_watt)
I tried excluding my hard drive from spotlight, as in the instructions, but this did not help. I am into my 5th attempt at a completely clean backup, and am only at 7GB (out of 241) after 6 hours. It says it will take 7 days to complete. I am hesitant to upgrade to ML, as I have seen many posts of people having similar problems with ML too, even when they did not have problems with Lion. Any other ideas of what to try?
Currently Being ModeratedOct 3, 2012 12:59 PM (in response to csims473)
To exclude your hard disk was not one of the three suggestions I posted. I said stop spotlight. That requires a terminal sudo command . All you have done is make spotlight start a new index on your HD possibly making the situation worse.
Look here for sudo commands
Currently Being ModeratedOct 8, 2012 12:59 PM (in response to csims473)
Apple just released an update (apparently this past weekend Oct 5 2012) that solves the problem (the update mentions this problem with Time Machine specifically).
Before applying the update, first-time Time Machine backup of my 10.7.5 MBP to an external USB portable drive was slated to take 53 days, despite formatting and reformatting the external drive a few times. After the system update was applied, Time Machine performs correctly, and it looks like it'll be done in a few hours.
Currently Being ModeratedOct 8, 2012 1:05 PM (in response to atlas3651)
I started my first TM backup the day before the update on Friday and it said it would take 14 days to backup 1tb via usb. Then I updated and resarted the TM and it initally said it would take 799 days!!! but then finished in about 15 hours. Big relief!