When I start the game, it crashes after about 3 seconds. I've never be able to play the game. I've already checked 2 times the data with steam, and I tried with several settings but it still doesn't work. I noticed that the launcher doesn't save the settings after I close it and the game is able to work on the other windows accounts of my computer. Could someone help me to make the game work correctly without using an other windows account ?

You can try to restore your system to an earlier time.

http://windows.microsoft.com/en-us/windows-vista/turn-back-time-on-your-pc-undo-system-changes-with-system-restore

You can also try running Steam, FO launcher and FO4.exe as admin. Make sure you are running under an admin account not a limited account.