Truly disable autorun:
1. The easiest and most effective means to truly disable autorun can be done via this simple autorun registry hack:

REGEDIT4
[HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\W… NT\CurrentVersion\IniFileMapping\Autorun…
@=”@SYS:DoesNotExist”
2.

To use this method, Open Notepad and copy/paste the following into a text file:

REGEDIT4
[HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\W… NT\CurrentVersion\IniFileMapping\Autorun…
@=”@SYS:DoesNotExist”

Save the file as something.reg. (You have to be sure to change the “Save File as Type” to “All Files” before saving, or Windows will try to save it as a .txt even if you typed in .reg.
3.

Locate the file you just saved and double-click the file to run it. You will receive a prompt asking if you want to add the data to the registry. Click yes to allow the modification.
4.

The above method nulls any request for autorun.inf and works on XP Home or Pro, as well as Windows Vista. Credit for this tip goes to Nick Brown.

If you opt to disable autorun using any other method, you will first need to install an autorun patch from Microsoft that allegedly resolves issues that cause autorun to run even after it’s been disabled (using methods other than the above recommended method).
5. XP Pro users who have installed the appropriate Microsoft patch for your system and wish to disable autorun using a method other than described above, follow steps 3 through 8 only. XP Home users begin at step 9. Vist