Hammer 3.4 help Thread

Whenever I try to drag an area in Hammer 3.4 it will always crash, this occurs with all tools, including the selection and block tools. I didn't have this problem when I was first using the editor. I've reinstalled several times to different directories but the problem still remains. Does anybody have any suggestions?
I'm have Windows XP, an AMD Athlon 1.8 processor, 256 RAM, and a GeForce 4 440 mx graphics card.

Collective.valve-erc.com

Thats the version, that I've got, I've looked around there for help to no avail. I can't post the same question on the forums there at the moment even though I've registered?!
Should I try an older version?

Problem sorted, kinda. I've been infected by a virus, aswell as hammer not working, neither does windows media player or Nero. Nero actually confirms that the exe has been edited by a virus, many folders have been set to read only too, and I can't change the properties either. Looks like it needs formatting!!