Interested to see what the fix is. What version and build of Windows is on the laptop?
For some of our legacy PBX software over IP I just use virtual box with a known working image. Hasn't let me down yet.
The Mitel programmer here gives me a Access issue at times and repairing the install does the trick for me.
It was imaged by our IT department and updated to the latest Windows 10 Pro/Enterprise, I could look Monday on exactly what version, but it should be the same as my previous laptop...
I am well aware of the Access issue, have to do the repair several times a week... It's annoying. I actually have VirtualBox with a Windows XP VM for some older software that is still required, maybe I will install it there if needed to get by.