You're barking up the wrong trees.
As Tom and I said, this is a corrupted accdb file on your computer. It happens.
It's one copy of the accdb you are working with. Get a clean, new copy, either from one of your backups, or perhaps retrieve a new copy from wherever you obtained it originally.
Your Outlook problems are a totally separate issue; nothing to do with this one corrupted accdb. I have seen that same cycle of "password being dropped" by Outlook for specific email accounts. It was episodic and hasn't recurred for many months now, though.
I can't address your other issue with the repair going wrong because that's also quite specific to your computer and software.
Returning to the original point. Sometimes VBA in accdbs does get corrupted. That happens, I suspect, in cases where you are actively modifying functions or subs while another function or sub is running, i.e. when the code goes into break mode. It is not highly predictable, but the correlation between making changes on the fly while in break mode and corruption is quite high. The solution is to make regular, frequent backups and be prepared to use them. Or, exercise greater discipline while modifying code.