FSX Taxi guide

I wonder if anyone can help me, I have Vista business installed on my computer and when I am running FSX. Without SP 2 or Acceleration the taxi guide works perfectly, when I have Acceleration installed and I switch on the taxi guide it flickers for a split second and disappears, this is very annoying as I find the guide useful at large airports that I am not familiar with. I wonder if anyone else has come across this problem. My computer skills are limited and I have no idea how to correct it.