Ensure that you have followed all steps for a complete SBS installation here.
When the RMS License Manager has been installed, and you have imported your SBS license .lic file, install CardExchange® Gateway on the same computer.
After installation, navigate to your CardExchange Gateway program files installation path (default installation is under C:\Program Files (x86)\CardExchange Solutions\CardExchange Gateway) and open the CardExchange.ini file in Notepad.
On the line LicenseServer=no-net from no-net to the local IP address of the license manager.
Note:
Saving these changes will require admin privileges. Open Notepad in Administrative Mode.
After saving, open CardExchange® Gateway. The title of the program will be labeled as "- CardExchange® Edition (Small Business Server)". If no errors occur, and CardExchange is running properly. You can now change the LicenseServer= to the address of your license manager IP address.