Super User is a question and answer site for computer enthusiasts and power users. It's 100% free, no registration required.

Sign up
Here's how it works:
  1. Anybody can ask a question
  2. Anybody can answer
  3. The best answers are voted up and rise to the top

A piece of software I installed recently has gone mad, and I can no longer boot Windows. How can I remove that application, or at least prevent it from running at startup? Neither Safe Mode nor Safe Mode with Command Prompt work. Is there anything I can do short of reinstalling Windows?

share|improve this question
up vote 1 down vote accepted

I don't know which Windows you are using. At least for Windows XP, you can make something like a Bart PE bootable CD, (Windows PE stands for Windows Preinstallation Environment), boot from the CD, load the registry hive (you will probably need the file named "system") using the Registry Editor from the boot CD, and remove the autorun entries manually. The registry hives are stored at C:\Windows\System32\Config\ (Source). There is a guide with graphics illustrations here.

The autorun programs are usually stored in these places:

The Registry keys most often involved with startup have the word "Run" in them somewhere. They are listed below using the abbreviation HKLM for the major key (or "hive") called "HKEY_LOCAL_MACHINE" and HKCU for for the hive "HKEY_CURRENT_USER"

  • HKLM\Software\Microsoft\Windows\CurrentVersion\Run
  • HKLM\Software\Microsoft\Windows\CurrentVersion\RunOnce
  • HKLM\Software\Microsoft\Windows\CurrentVersion\RunServices
  • HKLM\Software\Microsoft\Windows\CurrentVersion\RunServicesOnce
  • HKCU\Software\Microsoft\Windows\CurrentVersion\Run
  • HKCU\Software\Microsoft\Windows\CurrentVersion\RunOnce
  • HKCU\Software\Microsoft\Windows\CurrentVersion\RunOnceEx

I don't know if this method will work with Windows Vista or Windows 7 installations; I have never tried to find it. But it definitely works with XP.

Another option is to use a registry tool in Hiren's BootCD, like

Registry Editor PE 0.9c - Easy editing of remote registry hives and user profiles.

share|improve this answer

If you can't get into safe mode and you've tried Last Known Good, the best option is to download one of the available 'rescue CDs'

System Rescue CD

Rescue CD

BitDefender Rescue CD

AVG Rescue CD

Download Kaspersky Rescue Disk

There are others.

Burn the CD, boot from it and try to repair the damage.

share|improve this answer

It's always a good idea to do a backup before you make any major changes. CloneZilla, PING, and Macrium Reflect are some of the free ones. Boot the knoppix live cd (free download). From knoppix you can brows through your windows drive and manually remove the program that automatically starts with your computer. Windows cant start a program that does not exist :-)

share|improve this answer

Your Answer


By posting your answer, you agree to the privacy policy and terms of service.

Not the answer you're looking for? Browse other questions tagged or ask your own question.