This happened yesterday, so today I was very careful to exactly follow the instructions in the tutorial. One again, when I reached the point to engage the VNAV,the light on the button will not come on, although LNAV works fine. So I took off anyway and controlled the speeds and altitudes by hand. I flew the whole course and LNAV followed it perfectly, but I had to control speeds and altitudes by hand all the way. I kept trying to engage VNAV without success. I managed to land the aircraft at destination by hand, and although the ILS did not engage it was my fault because I forgot to dial the frequency. I landed 2/3 of the way along the runway, because I had to pitch down seriously and turn off the AP when I realized that I was not following the glideslope. A nice touch is the little indicator that shows you how high or low you are with respect to the plan, which allowed me to make my descent pretty much according to plan until I hit the glideslope and assumed it would lock in (it didn't). Anyway unless someone can figure out why the darn VNAV will not engage, I cannot use one of the best features of the plane. I had both FDs on and religiously followed the settings in the tutorial step by step until the VNAV failed to engage. I checked a bunch of other settings, but I can't figure out if any of them are off. Henri

OK, it is a bug! I restartes FSX and reloaded from the FMC the panel settings that I had saved, pressed exec and VNAV and the VNAV light came on! YIPPPEEEE.... Errr...I doubt that this is the cause , but I had neglected to do the changes to the FSX.cfg file that are given in the introduction manual, so I did them before I did the above. Anyway if it happens again I will know what do do. BTW, that darn file is VERY hard to find - it is buried very deep in the most unlikely place, and I could only find it by doing a number of searches. Great airplane - and now to do the rest of this tutorial... Henri

OK, it is a bug!

I've had the same problem a couple of times; in my case switching to LVL CHG (even when on the ground) seemed to "wake up" VNAV which was then able to be switched in.