How to enable task manager in xp

[vikasg03]

Hy
I m using windows xp prof . I don't know how or when my task manager,regedit disabled. I m the only one who use the system. may be through virus or any 3rd party s/w,but without my knowledge. Now whenever i press Ctrl+Alt+Del msg comes "task manager disabled by administrator" . There is only one default a/c (admn) without any password. Now how can i enable the task manager. my regedit is also disable so cannot enable through regedit. Any free/trial s/w which enable this?
vikas

[Lucky_star]

Use Remove Restrictions tool to enable all that you lost