This started with (what I thought to be) just a 757-related problem, but it turns out that *all* my CS aircraft now CTD after selection, on clicking to "fly".

This is with the 737, 757 and 777 - all the latest/correct (P3D4) installers.

So far, I've repeatedly uninstalled and reinstalled (as admin) with and without firewall and a/v - all to no avail.

This is with P3Dv4.5 and Win10 Pro x64 (fully up to date) and latest FSUIPC (paid/5.153).

I don't get a serial number prompt when reinstalling. Maybe I have some sort of general CS activation issue <???>.

All my other "study level" aircraft (other, another company, A2A, QualityWings etc.) are running fine, so I don't think I have an inherent P3D or system problem.

What to do? H-E-L-P!!

Do you need any more info?  TIA,

Adam.