Mike Cisar wrote:
Essentially the user will have a number of messages in their mailbox (today for example 13) the download of mail will go just fine until one particular message and then the download will just stop, eventually returning an error message. Trying to receive mail again will retrieve messages 1-9 again and fail in the same spot. If you log in via IMAP and delete the following message (ie. the message after the one that was last received) you can then POP for mail again and the remaining messages in the mailbox will download.
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Any thoughts?
Yes, virus scanner and firewalls. Does the user have such on his computers? I've experienced some cases where such programs inspect the traffic between MUA and server and hang if they encounter unexpected line terminators (single LF) or null bytes.
A windump log from the customers computer when receiving such a message would be very helpful in any case.
Jürgen