This is caused by a bug in Outlook/Express.
The email does not have an ending tag, so outlook can not tell when the end of the email is so it continually keeps trying to download the email. Eventually it hangs and times out.
Spammers are now sending these emails on purpose to create some havoc out on the internet.
The simplest and quickest way to fix this is as follows.
1... Login to the webmail area www.yourdomain.com.au/webmail
2... Make sure you use the full email address as the user name, eg. email@example.com not just info
3... Delete all the emails that you do not want, ie spam etc.
4... Now try outlook/express or whatever your mail client is again.
5... If it still hangs then the bad email is still on the server, keep deleting the emails until your mail client works again.
You are now back to normal.
NOTE: This is not an error on the mail server it is more to do with outlook/express/client and antivirus programs.
Outlook hangs when downloading messages, causing the same message to be downloaded many times in a row and other messages cannot be downloaded. Spammers and hackers have found new ways to disable Outlook users. Outlook as well as Outlook Express is not able to handle emails with improperly formatted message-ID headers or just with received headers.
Emails like theses are sent to 'abuse' or 'break into' Outlook. They do not contain any mail body or subject or from/to headers. Microsoft has not addressed this problem yet because the messages do not violate RFC standards. This is the reason these messages are able to get past the RFC822 content filter in Apexhost/Merak Mail Server. Apexhost/Merak Mail Server is compliant with all RFC standards and once a standard is set for filtering these types of messages our developers will adjust the core product to filter out these types of emails by default.
Apexhost is currently working on a Content Filter to stop this from happening.