that particular error message isn't familiar, but the overall scenario is.. you're trying to concurrently use access with paradox, which will almost always result in problems.. access doesn't use the bde directly, so it does not share and manage files the same way..
yes, the office 2010 issue makes sense, because office 2010 no longer pretends to support paradox.. yes, the lock file and reboot errors make sense, because of what I said above.. you have options, you just need to pick the one(s) that work for you:
use access with the paradox data only when nobody is using paradox
use access on a copy of the paradox data
export text files from paradox that access can work with, instead