How to unprotect regedit?

Please clarify your question.

Regedit is program used to edit the Windows Registry. What makes you think its protected and from what? Why do you want to unprotect it?

This could be a sympton of that nasty virus going around that makes many tasks display the "disabled by the administrator" message.

You can try this script: Disable/Enable Registry Editing Tools (http://www.dougknox.com/security/scripts_desc/regtools.htm)

Someone already adjusted my laptop, so the laptop can not read the flash disc (USB). I was already tried to fixed it by change the number (from 4 to 3) of Start (in the USBstor entering from regedit) but this action was useless. At the screen was a warning : Cannot edit start:error writing the value`s new contents.