As I need space on my hard-disk I decided to de-install FS2002 using the official desinstallation routine.It happened exactly what I feared: Now I cann't start FS204 anymore. It says something about terrain.cfg and scenery.cfg missing and that I must do a Fs2004-reinstall !I tried the Fs2004 install. It says that I must first do a desinstall!The problem is that I have added manually all my ai-traffic with planes(fsp,aia etc) and also many many afcad files and other planes .So Is there not a way getting out of this without complete reinstall?If I do a desinstall-reinstall will this delete everything or will the manually added planes remain?What must I save eventually: the afcad files (from Addon Scenery/Scenery), the traffic files (aircraft, flightplan and Airport, I have them in a separate folder) , the aircraft and what else?Would be very happy about any help or idea.Thanks in advanceGuy

I have made some research now and found out that there are two methods used: 1)Delete Fs9.exe and then install FS2004 right over the existing one. After what I read with this method the add-on files remain untouched. 2) Change the name of the existing Fs2004 folder and do a new install and then drag the add-on files from the old to the new one. The first method seems easier to me. I am asking myself which one is the best? I would not like to have to re-install the add-ons like Pmdg, Pss etc. Guy

Hi Guy,I would suggest you do number 2. That is the only way you can be sure that your add-ons are safe. Its just a rename of the FS2004 directory. After that you copy all the stuff in the renamed directory over the new FS2004 directory.Greetings Harry

Thanks.I have chose solution 2 as you suggested.Guy

I have found that when I uninstall FS,it only uninstalls what originally came with flight sim. Leaving most of my addons intact.It dosn't remove folders like: Aircraft,Addon scenery and other folders with other then defalt content.The only exceptions are, Fs9.cfg,trafic.bgl,and the defalt aircraft. For the flight plans, just recompile with TTools and it the same as beforeKenrick

Thanks for the information.Guy