Well, let's start with the obvious. Did you double-check and make sure that's the name of your file, because that's an old MDB file extension? Are you sure you're not working with an LACCDB file?

All the lesson From beginning 1- 9 and Expert 1 - 19, and even some lessons in Expert 20. the database use end in .accdb. I can leave without Lesson One in Expert20.

You're right - the current course databases are ACCDB files. Expert 20 Lesson 1 is an older lesson that was originally built around the MDB format.

You shouldn't have to skip it. Just use the actual .accdb database file wherever the lesson refers to an .mdb file. Do not use the .laccdb file - that's just Access's temporary lock file.

If changing the filename/extension to .accdb still gives you that error, post the exact step or line of code that triggers it and I'll take a closer look.

Thank you!