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The problem is caused by a bad message.
Open Tools/Accounts/that account/Options. Check Allow online access. Now you'll see a server account for the account in your Folder list. Go to it. You're now looking at the messages on the server. If you know which is the problem message (the oldest one there if you don't normally leave messages on the server, or the oldest one with a jagged icon indicating not downloaded otherwise), turn off the preview pane in View menu (or command-\). Select the bad message and delete it. Now everything will be fine - send & receive all.
or loginto your email inbox using http web and delete long and unwanter emails.
it will resolve theissue.
Ask me if need more information.