Excluding domain names from the Sender ID filter does not take effect after you run the Set-SenderIDConfig cmdlet on an Exchange Server 2007 server

Symptoms

You use the Set-SenderIDConfig cmdlet together with the BypassedSenderDomains parameter on a Microsoft Exchange Server 2007 server to exclude domain names from the Sender ID filter. In this situation, this setting may not take effect if the senders' domain names include capital characters. For example, you run the following command in Exchange Management Shell:
Set-SenderIDConfig -BypassedSenderDomains "contoso.com" -SpoofedDomainAction Reject
If the sender is <someone>@contoso.com, the message is delivered without the Sender ID filter. However, if the sender is <someone>@Contoso.com, the message passes through the Sender ID filter and may be rejected.

Cause

This problem occurs because domain names that are in the Bypassed Sender Domain are case-sensitive.

Resolution

To resolve this problem, install the following update rollup:
2279665 Description of Update Rollup 1 for Exchange Server 2007 Service Pack 3

Status

Microsoft has confirmed that this is a problem in the Microsoft products that are listed in the "Applies to" section.

More Information

For more information about the Set-SenderIDConfig cmdlet, visit the following Microsoft website:
General information about the Set-SenderIDConfig cmdlet