You might mean mnyob99.dll.
1. Copy your *.mny and *.mbf files to other media, such as a USB flash drive, in case something fails.
2. By default, Money Plus keeps your four latest backup files that include the time and date as part of the filename. So it may be that there was a problem, and the latest backup file contains that problem.
Close Money. In Windows Explorer, browse to your folder that has your backup files. Double-click on the second-newest backup file (*.mbf). That will open Money and start the restore dialog. If you have hope of fixing your current *.mny file,
(as low as that hope may be), you can choose a new name for the restored file.
3. If the problem persists, it may require an installation of Money with Money Plus Sunset. As a test, I would copy sample.mny from your C:\Program Files\Microsoft Money Plus folder to your Documents folder. Open that file. If that fails, there is a problem
with the installation. Check back before installing.