I am having the saaaaaaaame problem. I do not use Yahoo Business Mail, but I do use Mail Plus and have had the SAME problem. I have reset the account several times. I have even deleted it and re-added it several times. No matter what, the full amount of emails will not be brought over to Zimbra. In fact the synch just stops midway through. The last time around, not even teh inbox would load or any of the other system folders. However, some (though not all) of my created folders synched. Is there a way to force the synch to resume? The only thing I have NOT done is completely uninstall Z Desktop and reinstall it. Oh, and I do have the build 1251, latest version. So ... other than tearing my hair out, can anyone think what I can do?