ArcMap 10.8

[hlbwelc]

Hello all. I am using ArcMap version 10.8.2. I am attempting to add data, an excel file, into my map. However I am receiving the error message "Failed to connect to database. An underlying database error occurred. Class not registered." 

I have never had this error message come up before, does anyone have a suggestion for resolving this?

Thank you!

[RhettZufelt]

Have you installed the Microsoft Access Database Engine driver?  You will need that to access Excel files from ArcMap.  Documentation here.

R_

[JimCousins]

RhettZufelt has provided the correct answer.

If you are still having issues, be aware that having the excel file open in Excel puts a lock on the file and prevents ArcMap from interacting with it. In addition, another instance of ArcMap that is open and points to the Excel file will put a lock on it, preventing interaction with it. Closing these links should enable access to the Excel file.