n-Command MSP Version 10.3.1 introduced an issue that causes device check-ins to cease to function upon upgrading. If your n-Command MSP server has internet access, it will have already downloaded this update and will show an "Update Available" message at the top right of the interface:
Do not update the software to this version. We will release a new version shortly which will resolve this problem. A software notification will be posted when this software is available.
If you have already applied this version, you can open a ticket with Product Support at www.adtran.com/submitcase and we will resolve the problem in your server.