Srdjan: We use FPD2.6 and we still have an old FPD2.0 application that are both working in WindowsNT 4.0. We have been using NT for about 8 months. The only library we use is Comtools 3.0 and it works flawlessly. We modify and maintain our "old" code using NT with no problems. If you have any specific questions, please ask.