Yes it was their fault... I read that they did something in the code that stopped FSNAV using certain things within FSX not sure of the nuts and bolts,FSNav doesn't work in FSX but that's not MS's fault
There seems to be no other prog that does the same job.
If I have one big gripe about FSX is cost... most developers are going payware and many cant afford it..I cant justify spending £20 on an add-on plane that quite frankly I could get for FS9, but you pays your money and takes your chioce. I doubt if I will go to FSXi as FS9 will see me through until I retire from FS
I have never seen on forums anything before like the FS9 V FSX debates. Just goes to show all that glitters is not gold!!!