Error: "The account number or software serial number entered is not valid, please try again."

Users of Sage 200 Professional on premise may receive the below error message when reactivating an expired serial number or there are 2 serial numbers that are swapped over.

To resolve this you need to delete the entitlement folder on the server machine which is located in C:\inetpub\Sage 200 App Services\Sage200SecuredServices\Entitlements prior to inputting the new serial number.

 NOTE: We communicated this to Partners and Developers on 10/01/2025, find out more here.