Could there be something amiss with the permissions on that folder? On Windows Vista and Windows 7, you might not have permissions to write changes to a file in the /Program Files directory -- so if you're moving your TW into (say) the folder where your browser is installed, the write may file -- while your backup write succeeds as long as the backup path is pointed elsewhere.
Assuming you're not trying to save in /Program Files or some UAC- protected location, you could right-click on the folder your TW is in, view "Properties," and make sure the folder isn't set to Read-Only access. -- You received this message because you are subscribed to the Google Groups "TiddlyWiki" group. To post to this group, send email to [email protected]. To unsubscribe from this group, send email to [email protected]. For more options, visit this group at http://groups.google.com/group/tiddlywiki?hl=en.

