I doubt that the two issues are entirely separate, but we don't have eyes on the network environment which makes diagnosing the problems more difficult.
In Post #1, you wrote, "Even if I copy the DB local I still get errors." Here, by "local" I at least thought you meant the laptop where the problem is. Correct?
In Post #18, you wrote, "On the laptop I cant even copy the file over get error invalid signature." That is the exact opposite of Post 1.
In the interest of making sure we are all on the same page, therefore, I want to be nitpicky about what is really going on.
Can you copy the Front End, i.e. the accdb containing forms, reports and VBA, of the split database application from the original computer to the laptop?
In post 1, it sounds like you originally could, and did, successfully copy the original unsplit accdb to the laptop (I assume that is what you meant by "copy the DB local".)
In Post 18, it sounds like you suddenly can't copy the accdb which contains only the forms, reports and VBA.
If that's the case, there are possible reasons for it, but rather than go off on a hunch, let's make sure we agree on the circumstances. For example, if someone else, i.e. another user, or even you, the developer, already have the Front End accdb open, Windows wouldn't let you copy it. But rather than go off on a tangent, please make sure we have the full circumstances nailed down.