NetBeans IDE 6.9[.1] - Upload files on save - re-enable for session
I personally did not find any option to re-enable FTP Upload for session, but if you go to Project Properties and set in the Run Configuration "tab" the option Upload Files to "On Run" or "Manually", hit Ok, and then modify it again to "On Save", then the FTP Upload on save is enabled again.
Hope this was helpful!
I close and open the project on netbeans 7.3. And syncing works again. This is faster than restarting the IDE.