It's intermittent, and mostly seems to affect outgoing mail. Blue bar that shows mail being sent gets about 90% of the way, and then I usually get a 10053 error message (connection aborted due to timeout or other failure).
Stuff I've done (in no particular order):
Changed mail server name to IP address
Changed SMTP port assignment from 250, to 25000, to 2500 (because I'm using a non-ISP email account)
Removed zonealarm, smartguardian and other memory hogs
Cleared out inbox and outbox
Increased network open timeout, network timeout and buffer size
Fiddled with SSL settings
Deleted ini and started afresh
Applied netgear wireless router firmware update
Updated Eudora to v 5.2
It appears as though this problem is not repeatable on the laptop (which uses the same ini file for Eudora). However, since this is an intermittent problem, that's neither here nor there.
THIS IS DRIVING ME UP A WALL.
What could it be? Anybody?