Hi, I'm Robert and I'll be helping you with your computer question.
what do you mean you lost access to the inbox?
can you still pull up the outlook ?
can you see other folders but not the inbox ?
This may be a bunch of things. including the inbox just hiding in the folder list or the entire email account just getting disconnected to a problem with the program itself.
I might be able to fix it very quickly if we do a remote session. But it can take a long time to just figure out what the problem is asking you to look at things for me.