rundll32.exe wont run. Registry problem?

**pzz76077** · 26 February 2010, 22:05

Originally posted by MonzaMike View Post

went to help out a friend who had been hit by a virus.

By the time I got there it looked like some of her anti-virus sw had cleaned it up, however there is a residual problem with rundll32 not working.

This means that a whole host of things won't work.

I'm pretty sure that the file isn't missing as I could see it in the system32 directory and even tried to copy the file back off the windows install disks.

Convinced that the registry is corrupted. There are loads of registry cleanup tools, but most need to be run after download, and the missing rundll32 stops that from happening.

Most of these registry tools just scan for free and then want you to pay up fix the host of problems that they detect.

Can anyone suggest a decent and free registry fix tool and/or suggest how I could fix this manually. There is lots of scaremongering against touching the registry yourself, but I'm wondering if much of this is the tool providers.

Have you tried booting in safe mode (F8) and running from the last good restore point??

PZZ

**Zippy** · 26 February 2010, 22:34

Did you uninstall rundll32 before you tried copying over it?

**xoggoth** · 26 February 2010, 23:03

Command prompt fsc might be worth doing to ensure file is what it should be:

http://unlockforus.blogspot.com/2008...ans-check.html

**Incognito** · 26 February 2010, 23:57

You haven't stated what O/S it is.

First steps, download Stinger, run in safe mode, reboot.

Repair system files (you will need install disks, if install disks don't have service pack slipstreamed then you'll need to patch the system post repair)

Xp

Vista

Reboot

If you need to repair registry post system

Xp

Vista same steps, but the backup files are located at "C:\WINDOWS\System32\config\RegBack"

**KNOW WHAT YOU ARE DOING BEFORE FOLLOWING ANY OF THESE STEPS, YOU CAN CAUSE SIGNIFICANT CORRUPTION BY MODIFYING THE REGISTRY INCORRECTLY**

Can anyone suggest a decent and free registry fix tool and/or suggest how I could fix this manually.

DO NOT use these registry repair tools, they are more trouble than they are worth and will very quickly make a major mess out of a minor one. If your friend has a legit copy of Microsoft then contact MS and get them to help you with the recovery process. As it's a virus, you should be able to go to them direct rather than through the OEM provider (i.e. HP etc)

https://consumersecuritysupport.micr...sk=diagnostics

**TykeMerc** · 27 February 2010, 01:02

You can probably do a good cleanup if you know what you're doing, it needs some experience and knowledge though.

Odds are that it will be quicker and less effort to copy the data files off and do a full format and O/S install.

**SueEllen** · 27 February 2010, 09:16

Originally posted by TykeMerc View Post

You can probably do a good cleanup if you know what you're doing, it needs some experience and knowledge though.

Doesn't need any experience but definitely needs knowledge

**VectraMan** · 27 February 2010, 10:19

Does RunDLL rely on anything in the registry? I can't see why. It's just a simple EXE that loads a DLL and calls a function on it (it runs the DLL oddly enough).

What happens if you try to use anything that needs RunDLL? The control panel for example.

Maybe system32 has gone missing from the path. That'd probably do it.

**xoggoth** · 27 February 2010, 14:11

No expert but I have the impression that it is the DLLs that use it that have to be registered to do so. The registry has entries like rundll32.exe\%system%root\sysetm32\van.dll,runVAN.

I managed to fix a bunch of problems once before by using the free Inno Setup installer to reregister some files that an idiot commercial address database program had overwritten with older versions. Seemed easier than messing about with regserver.

If you can discover which DLLs/OCxs a non working app requires you may be able to make up a script to reregister them. I could post a short sample script if you wanted to try that route.

**MonzaMike** · 28 February 2010, 21:17

Originally posted by VectraMan View Post

Does RunDLL rely on anything in the registry? I can't see why. It's just a simple EXE that loads a DLL and calls a function on it (it runs the DLL oddly enough).

What happens if you try to use anything that needs RunDLL? The control panel for example.

Maybe system32 has gone missing from the path. That'd probably do it.

Thanks to all for the responses so far.

Spent a little more time with my friends computer this evening.

Trying to run any of the Control panel apps produces a dialog stating c:\windows\system32\rundll32.exe Application not found

I also get a similar error if I click on System Information from My Computer, so I can't check the PATH environment settings.

I can look at PATH from a command window and it does include this directory, so think that is OK.

Now think that the application not found must be referring to the app that rundll32 is trying to execute.

Found some limited examples of how to run rundll32 from a command window, for example to show the windows version and this worked.

Another curious issue is that if I try to run IE from the start menu I get the "run with" dialog box (The one when windows doesn't know what application to execute to manage a particular file.) However if I run an existing IE shortcut on the desktop then it works fine.....

Found a useful disagnostic tool but when I download this, or any other apps from the internet, it downloads OK , but running the downloaded app fails.

Any more suggestions?

windows repair is beckoning

rundll32.exe wont run. Registry problem?