Your game is patched to 1.63, right ?
See if this helps. It will close down all unnecessary program to see if there's a conflict with anything.
- Close the game (kill it if necessary)
- Click Start or press the Windows key and R, click Run, type msconfig, and then click OK. (could be different depending on your OS)
- Click on Startup.
- Select disable All.
- Click on Services.
- Check the box that says Hide All Microsoft Services, then Disable All.
- Apply, then restart your system.
This is more for troubleshooting. When using the computer for other things, you should enable them again.