If you are getting EventID 210 on your SBS 2011 server – with a message like…

[message_box title=”Event ID 210″ color=”red”]One or more of the messages (message number) were left in the ‘[accountname]’ account on the POP3 Server ‘[servername]’ because they are larger than the maximum acceptable message size (the largest message is [messagesize] bytes). You can either connect to the POP3 account and retrieve or delete the messages manually, or increase the maximum acceptable message size in Exchange Server.[/message_box]

Then you can fix it by opening the Exchange Powershell Management Tool…

And performing these commands which will change the maxmessage size up from the default 10mb to something more realistic (50mb/message).

set-receiveconnector “Windows SBS Fax Sharepoint Receive [servername]” -maxmessagesize 50mb

Crazy I know – but you need to change this one too for the change on the Pop3 connector to work!

set-receiveconnector “Windows SBS Internet Receive [servername]” -maxmessagesize 50mb

set-receiveconnector “Default [servername]” -maxmessagesize 50mb

After that the messages will happily roll in and the errors will stop. Unless someone decides that a 50mb attachment to your client is achievable…