We are having email messages bounce back on size limits (message is larger than current system limit - 5.2.3). Have applied both the Global Setting and the virtual SMTP setting to increase message limits to 40000KB per Knowledge Base Article 322679) but still getting bounce back on a 4 MB attachment to a message. Have stopped and restarted exchange services after changing setting but this did not help. 1. Are we missing something about message size limits?2. Do we need to reboot server for changes to take affect?Thanks.

4MB is really 4096KB, or 4194304bytes. Could that be it?

Not really as we increased limit to 40000KB and message of approximately 4MB or 4000KB still bounced.

You have just 1 exchange server and its the "reporting server" in the NDR?

That is correct.Eric

Any other product or edge appliance that could be blocking the message (other then Exchange). Maybe it's the recipient's size limit not yours.

No. The error message is clearly coming from our exchange server. Thanks anyway.