You may see QuickBooks stop responding during a Rebuild after updating QuickBooks 2011 or Enterprise Solutions 11.0 to R8. You may see this problem after a backup fails and QuickBooks suggests running the Rebuild Data utility.
We are working to resolve this issue. There is nothing wrong with your company data file. You may continue to use QuickBooks until the issue is resolved.
This article provides instructions on what you do now, as well as an option for you to be contacted once the issue is resolved.
Temporarily turn off the verification option to complete your backup until the permanent solution is available:
Your backup will complete using the Quicker Verification option.