This is unfortunately still an issue in 22.214.171.124.
It only happens for system backups (not for the database ones)
The best way around it (except for the patch, that’s too technical for me), that I’ve found:
- to have magento-cleanup.php ready in your main directory: (http://www.magentocommerce.com/wiki/groups/227/resetting_file_permissions)
- do the backup,
- let the error occur happen
- chmod the magento-cleanup.php file to 755 (use Filezilla or other FTP program)
- run the cleanup file (by browsing to it in your browser)
This will fix all issues and bring your store (backend and frontend) up online again.
Still,l it’s unfortunate that the fix wasn’t included in 126.96.36.199, let’s hope it will go in the next one.
You would expect that magento-cleanup.php sets all your files correctly so the issue wouldn’t occur in the first place. Too bad: for me it still gives the same error when doing the backup