If you are a vista user, here is a list of things you can try to get TFW working:
Run the program in:
Compatibility for XP
Disable visual themes
disable desktop composition
disable display scaling
Reinstall, running the installer as Administrator (right click and run as admin).
Run the updater as Administrator.
Disable Data Execution Prevention. To do this, type without quotes "bcdedit.exe /set nx AlwaysOff" into command prompt. To enable it again type "bcdedit.exe /set nx AlwaysOn"
Disable User Account Control.
Run the game without running the launcher.
Install the latest Direct X, avalible here: http://www.gamesforwindows.com/en-US/Ab ... X10-a.aspx
Disable your sound drivers: Realtek and Creative both cause problems at times.
Fully update vista.
Buy/download Vista Service Pack 1.
Delete both/either/or pperms.xml and pref.xml in the /helpers directory then run launcher.
Install the latest graphics drivers for your card.
In the control Panel, go to Problem Reports and Solutions->View Problem History. See if TFW has caused any errors here. Mine did once, due to having 2 installations of TFW, the error been incorrect side by side configuration.
Create another account and try login in with it.
XP users, try the same thing, just ignore vista specfic advice
Windows 2000, nt, 98, 95 etc users need to buy better computers or something.
Linux users, if you can even get TFW to work, tell me how - ubuntu throws hissy-fits when i try
Mac users..... just dont even try.