Hi Folks -
Found this valuable forum while wrestling with another issue. Maybe I can return the favor.
I have the same problem with ACT emails getting stuck in the outbox and refusing to respond to the command to send them.
I now use ACT! 2005 ver. 7.0.1 which addressed some, but not all, known ACT! 2005 bugs.
This is a known problem that the folks at Best Software say they're looking into.
If memory serves, the problem has to do with the difference between previous versions of ACT and the current version interact with your mail server.
Try backing up your system and setting up another email account.
Check with your email server and see if the require authentication prior to log on.
Then under ACT!>Tools>Preferences>Email>Setup.
That should invoke the Email setup wizard, and somewhere near the end of the 5 or so steps it asks whether you need to authenticate with your email server, or not. Reply per the answer re. authentication received from your email server. If it doesn't work, they it again answering the check box the opposite way.
FWIT, I run 5 different email eddresses from within ACT! 2005 and only have done this with one email account. So when I send a response on any of the other 4 accounts it still gets hug up in the outbox until I move the copy to the outbox of the one account I've reconfigured, and then is sent.
HTH,
Boathead