How to fix error message "Class not registered" in Windows 7 64 bit?

Hi,

Have you made any changes to your computer prior to the issue?

Method 1: Run SFC scan. System File Checker (sfc) scan will make Windows replace corrupt or missing system files on your computer.

 Steps to perform sfc scan:

a. Click Start, click All Programs, click Accessories, right-click Command Prompt, and select Run as Administrator.

b. Click Continue or supply Administrator credentials if prompted.

c. In the Command Prompt window type the following, and press Enter:

sfc /scannow

Refer this KB article for more information:

http://support.microsoft.com/kb/929833

Method 2:

Check if the issue persists in safe mode, to boot the computer in safe mode follow the below steps:

a.     Restart the computer and press and hold F8 key (Press and hold f8 key before the windows logo).

b.     From the advanced boot option select ‘Safe mode’.

Link you may refer to: Start you computer in safe mode:

    http://windows.microsoft.com/en-US/windows7/Start-your-computer-in-safe-mode

One way I have been able to fix this with our users, is to recreate their profile from scratch.

1. I reboot the PC.
2. Then login with the domain admin account.
3. I rename the users folder that is having the issue and delete the users registry entry in {HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows NT\CurrentVersion\ProfileList}
4. I also rename the users profile folder in the DC this is the username.V2 folder.
5. I log off their PC and have user log in.
6. After they authenticate their desktop looks brand new with none of their files, so I log back in as admin and copy over their files from the local users folder I renamed.

This is the only way I have been able to fix this in a domain environment using Windows 7 desktops. I hope this helps.