How do I 'lock' my xp computer without using the screensaver?

I’ve noticed that a work colleague’s computer is locked when he leaves for work (rather than completely logged out, since he’s the only person who uses that physical PC)

I can lock my own by setting a password on the screensaver, but is there a simple way of locking it without waiting one minute for the password-protected screensaver to lock it for me?

Ctrl-alt-delete, Lock Computer.

I may be being incredibly dense here but i’m using Windows XP Pro and can’t see this option on the Task Manager, where abouts is it?

me neither. I tried ctrl-alt-delete before even compising the OP.

Or ‘composing’ even.

Windows-key + L will do the trick.

I think I have found the answer

Note that you can still lock the screen if you use the Welcome screen (assuming your account has a password), it’s just not one of the options that comes up immediately when you hit ctrl-alt-delete. In Task Manager, it’s the “Switch User” option under the “Shut Down” menu, or Windows-L, as Catalyst points out.

The reason for the difference in behavior depending on whether you have the Welcome screen enabled is that the “Windows Security” screen is necessary for environments where good computer security is a requirement, but more casual users are used to the Win9x task-manager-like thing popping up when you hit ctrl-alt-delete. The Welcome screen is inherently less secure than the standard “press ctrl-alt-delete to log on” screen, so Microsoft assumes that if you enable the Welcome screen, you’re obviously not in the category of user that needs the extra security of the “Windows Security” screen, so enabling one disables the other.

My post would probably be a little clearer if I used the word “whereas” instead of “but” in the first sentence of the second paragraph.