XFOR: Random Inbound Messages Appear with Empty "To" Box or Message Body

When Microsoft Exchange version 4.0, 5.0, or 5.5 is installed with Internet Mail Service behind a Cisco Secure PIX Firewall version 4.2(2), inbound messages may randomly appear with an empty To box or an empty message body. In some cases, the message body may appear in the header, or the message body may contain a long string of X characters.

This behavior can occur if the version of Cisco Secure PIX Firewall that you are using is not fully compatible with your Exchange version, Internet Mail Service, or both.

To resolve this behavior, upgrade to Cisco Secure PIX Firewall version 4.2(3) or later.

The third-party products that are discussed in this article are manufactured by companies that are independent of Microsoft. Microsoft makes no warranty, implied or otherwise, regarding the performance or reliability of these products.

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