How to register the Sage 300 DLLs and OCX files Resolution To run Sage 300 RegAcc.exe (Register Accpac) to register DLLs and OCX files, log into the computer as a Windows Administrator.Browse to the Sage 300 Runtime folder, right-click RegAcc.exe, and select Run as Administrator.This resolves errors related to Sage 300 registration, such as “invalid database specification” or component errors. Sage 300 Request Support