To increase the send and receive limit for all users on Exchange there are 3 settings that need adjusting. Global Transport, Receive Connector, Send Connector.
Global Transport Settings
To check current configuration:
Get-TransportConfig | ft MaxSendSize, MaxReceiveSize
To set a new limit:
Set-TransportConfig –MaxSendSize 30MB –MaxReceiveSize 30MB
Receive Connector Settings
To check current configuration:
Get-ReceiveConnector | ft name, MaxMessageSize
To set a new limit:
Set-ReceiveConnector “Windows SBS Internet Receive Servername” –MaxMessageSize 30MB
Send Connector Settings
To check current configuration:
Get-SendConnector | ft name, MaxMessageSize
To set a new limit:
Set-SendConnector “Windows SBS Internet Send Servername” –MaxMessageSize 30MB