[Capt.Mouath]

Hello Khalid ..

Just do the below steps:
1- Uninstall FSX completely
2- Download this tool from Microsoft .. DOWNLOAD ..
3- Run it and after that click on Accept if required
4- Microsoft will download and install the Fix It Engine on your computer
5- Select the first option which is: "Detect problems and apply fixes for me (Recommended)" from the box
6- Click on Uninstall
7- Select the program you want to uninstall which is FSX and complete the process
8- After you finished from the tool re-install FSX from A to Z

i hope that works and everything will be fine .. enjoy
Goodluck :-)