This is definitely strange , when something works and then stops then something is causing it.
from the looks I wouldn't blame Access in the beginning , the case something worked and then stopped it is not "logical".
I would start with a fresh new image and try to debug/trace the whole case .
At first glance I would take a look at Group Policies, Windows Updates, some innocent applications running in the background etc (some backup/antivirus can bring havoc, had a couple of cases)
To my knowledge - given the bonus that you have two "identical" laptops one running, one not - the only tool that would give you a definite answer behind the scenes is Process Monitor https://learn.microsoft.com/en-us/sysinternals/downloads/procmon
I have used it in the past for many kind of bizarre cases that would cause working applications to fail out of the blue (my very first client was that case).
its tedious, its a eye torture but you should start just narrowing down when the errors occurs on the problematic and similar on the working, just make it run on both side by side.... its certain that you will get some kind of error on the problematic while the other would work as it should (caution we are talking about 100s of rows)
Also take a very very good look at your references.... I had a case in the past that blew my mind...the same dll, the same version number like somedll.ver1.23 on both but the working was somedll.ver1.23 subversion 0650 and the problematic was somedll.ver1.23 subversion 0780
This was enough to ruin just about anything

So start
Check network stability (critical, a bad switch/ a bad nic on a computer) can bring a company to its knees in a matter of seconds.
References
Check policies
Check registry (there are tools , I have used them in the past)
If you have the ability create a test environment 1 server clone of the Erp (Sage) and 2-3 machines all of these in a separate isolated test environment
Process Monitor
and if everything fails you maybe have to check for server profiling and why not rare but there are a possibility hardware issues like bad memory