inscatolati - Get out of the box! :)

Symptoms: customers accessing their own mailboxes report Outlook crashing or the connection being dropped, with a message similar to "Your server has unexpectedly terminated the connection...". You look into the user mailbox, and there doesn't seem to be anything strange. If you look carefully, you should see one or two really small mails.

It seems like Norton Antivirus causes Outlook to crash or the connection being dropped when a user receives a mail without body and no \n after the headers.

The problem has been reported to the CERT as a potential DoS, and Norton seems well aware of that problem. However, no fix is provided.

Two possible solutions:

• configure your mail server to always add a \n after the headers of any received email, even when there is no body.

• disable some Norton Antivirus options. Take a look at this issue on the Symantec Support site and to those instructions for more useful data. The links: Microsoft support and C4 Net support might also contain useful info.

We have also observed that certain kind of mail with charsets others than ISO-8859-1 or ISO-8859-15, with mime errors and/or the '\0' character, might cause either Norton or Outlook to crash. However, we haven't been able to isolate the problem so far.