Thunderbird has worked fine for several years. Suddenly cannot send mail or receive incoming e-mail to my AT&T Yahoo account. Send Now button is replaced by a Send Later button. If I set for Restore Default Set in View\Toolbars\Customize the Send Now button does reappear but any mail I attempt to send goes straight to the Unsent folder in my Local Folders and is not actually sent. Under the File drop down menu Send Now is grayed out. Reinstalled over the top but it did not help. Win XP System Restore did not help. Win XP w\Thunderbird 2.0.0.12. Any suggestions short of a TBird uninstall\reinstall?
Sounds like you somehow put yourself into offline mode. Either use File>Offline and toggle Work Offline or click on the little offline/online icon in the lower left.
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