I would like to know why msrd3x40.dll v4.00.9801.7 is no longer working with Microsoft Access 97 (knowing that msrd3x40.dll v4.00.9801.5 is working).
From: https://allthings.how/fix-microsoft-access-unknown-database-format-error-after-windows-update/
"Getting the "unknown database format" error when trying to run an app that is built with the Microsoft Access 97 database MDB? The likely chances are you recently updated your computer to the latest
Windows 10 January 2019 Update which appears to have an issue with the Access 97 databases.
Thankfully, the fix is simple. You need to download an older version of the msrd3x40.dll file and replace it with the new version released with the January update."
Thank you