To increase the connection restriction limits set in MS Exchange
- Open EMC (Exchange Management Console).
- Select the "Server Configuration" node on the nav tree.
- In the centre panel right click the server and select properties.
- Open the "Limits" tab and configure the section labeled "Connection restrictions".
- Increase the value to an appropriate number.
- By default the settings are:
Maximum concurrent outbound connections: 1000
Maximum concurrent outbound connections per domain: 20
Restart the "Exchange Transport" service when finished modifying these settings.