backup and common area
I made some tries; if I select 'mySQL database' all works fine, but when I select too 'web data' backup stops and returns the download window with 209 byte of save set.
Then I suppose Falkso says the true about the backup. Infact I suspect the problem is connected to a common area where I put the source to share TYPO3. The source is owned/grouped by root:root and it is linked by some symlinks from the single sites.
Could be that the backup utility follow the links, just arrived in the common area where root is the owner stops it.
I remember that in the old times there was a similar problems connected to the backup and follow symlinks.