you can search the web for some hacks that work on some versions of Access, but the whole point of the password is to keep people out.
Its no good if you can defeat it.
I've searched quite long time and still not getting any software to break it.
Some of the software need to paid.
that may be your only solution if you want in.
.accdb uses a much higher level of encryption than .mdb - it is almost impossible to break it without a supercomputer and plenty of time.
If you decide to pay a company, make sure they are reputable and don't just take you money and then say they can't break it. And before you ask, I can't recommend anyone.