I haven't ever heard of the file but if it indeed is what you say it is, then you can most definately copy it from any other computer with the same OS version.

Good luck and keep us updated on what happens!

Windows Registry Editor Version 5.00

[HKEY_CLASSES_ROOT\.msc]
@="MSCFile"

[HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Explorer\FileExts\.msc\OpenWithList]

[HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Explorer\FileExts\.msc\OpenWithProgids]
"MSCFile"=hex(0):

[HKEY_LOCAL_MACHINE\SOFTWARE\Classes\.msc]
@="MSCFile"

Copy and paste the above into a text file, save it as a .reg file, then double-click the file to merge it into the registry.

I'm not sure that's going to solve your problem, however. I'm not sure how the Certificate Manager relates to the defrag utility. Have you tried replacing certmgr.msc?

Also, you say your computer is infected? infected with what?

C:\WINNT\system32\dfrag.msc

Microsoft Management Console. If you have it and associate it with that, the defrag utility will work.

If you can right-click on it, and choose a program from a list if one of the programs is Microsoft Management Console, it will work. In the system32 folder there is a file called mmc.exe. Disk Defrag needs to be associated with the Management Console.

Also, I don't think that M/S defrag does such a great job, there are so many better ones including:

• PerfectDisk
• Defragmenter Pro Plus
• O&O Defrag Professional Edition
• DefragMentor Premium
• Defrag for Windows 2.2
• Vopt XP
• Diskeeper Home Edition
• MindSoft Defrag
• Diskeeper Lite

The association somehow got screwed up for .msc extension. Go to the windows\system32 folder and look for mmc.exe (Microsoft Management Console).

If it is there, go to tools, folder options, file types and look for the msc extension, highlight it and go to the change button, browse to the system32 folder and click on mmc.exe.

Or click on the defrag.msc and open with, browse to the system32 folder and mmc.exe and don't forget to check the box for open all files like this with this program.

If you don't find mmc.exe in the system32 folder, copy one off of another computer and paste it into the system32 folder on the problem machine, then associate the msc files with it. 😎

This thread perfectly applies to my case, I am in the same situation and have gone through all the above steps. I have the dfrg.msc file in my system32 folder and it's associated with MMC.

FYI the error message I get is:

MMC cannot open the file c:\windows\system32\dfrg.msc.

This may be because the file does not exist [it does], is not an MMC console [it's associated w/ MMC], or was created by a later version of MMC [possible since I've recently reinstalled XP as well as performed a failed System Restore!]. This may also be because you do not have sufficient access rights to the file [I'm logged in as administrator].

Do I need to update MMC? If so, how? Might it be a missing registry key?

Hey absoluten I had the same problem, I did a repair install and when I tried to use Windows defrager after I got the same message as you. I found a fix! go here

https://download.cnet.com/Microsoft-Management-Console-3-0-for-Windows-XP-KB907265/3000-2206_4-10741230.html

and scroll down a bit over half way and download and run WindowsXP-KB907265-x86-ENU.exe package. Its the latest version of mmc (mmc 3.0)and I'm almost certain it will fix the problem your having. please post back if it does.

Here is the solution to getting the defragmenter working again. You need to re-register the defragmenter software components:

Method 1

1. Click on Start, Run, and enter regsvr32 dfrgsnap.dll.
2. Click on Start, Run, and enter regsvr32 dfrgui.dll.

If this doesn't resolve the problem, try Method 2.

Method 2

1. Click on Start, Run, and enter %windir%\inf. This should open a folder named Inf.
2. Locate the file named dfrg.inf (it might be listed as just dfrg.)
3. Right-click this file and click Install.