There is only one file type that uses the .OFC extension:
Open Financial Connectivity File
Financial data format developed by Microsoft as an open format for exchanging data with other financial programs; replaced by the .OFX format in 1997 and is not supported by MS Money 2005 or later.
Microsoft discontinued sales of Microsoft Money in June 2009 then ended support for the software in January 2011.
Updated: May 1, 2020