Class Not Registered

It is really tough to answer your question with so little information.  What model computer do you have?  Which version of Windows are you running?  Specifically what are the "certain programs or drivers" you are trying to install?  Provide somemore information, and perhaps someone can help.

Steve

Windows XP on a Dell 2350.I'm getting this when I try to install things from the Dell Rescource CD's mainly.

Jojo,

Thank you for using the Dell Community Forum.
This error is usually caused by a replaced *.dll file or corrupt *.dll file.
This error can happen with any software application, it is not restricted to one perticular software package.

1.Use system restore to go back to a date before the problem started.
2.Use the SFC utility to verify the system files.
3.Perform a repair install of XP.
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Using System Restore.
1.Click on (Start,Programs, Accessories,System Tools, System Restore.)
2.Check the box for (Restore my computer to an earlier time)
3.Click Next.
4.Choose a (Restore Date.) before the problem started.
5.Click Next.
6.Click Next again.
7.The system should restore and reboot.
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Information:
To try and fix problems with Windows corrupt files, please try using Windows SFC.

Solution:
1.) Put your WindowsXP reinstall CD in the system.
2.) Click Start, Run.
3.) Type in ( SFC /Scannow )
4.) Click OK, and the system will start checking the system files.
5.) If any errors are found the system will prompt you to replace these files.
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How do I perform a Repair Reinstall of Microsoft® Windows® XP?

Discussion
Windows XP includes a new reinstall option, the Repair Reinstall. This option should be used when you have determined that the operating system files are corrupt, but you do not want to completely format the hard drive and reinstall the operating system.

What a Repair Reinstall Will Do
Delete all of the files normally installed by Windows XP.
Reinstall those files from the Windows XP CD.

What a Repair Reinstall Will Not Do
Completely rebuild the registry. A Repair Reinstall only writes to parts of the registry used by Windows XP. It will not completely rebuild the registry.
Delete applications and user settings. A Repair Reinstall will generally leave applications and user settings in the state they were before the Repair was attempted. All applications should remain functional, and all user settings should remain the way they were.
Fix issues caused by corrupt applications or user settings. Since the Repair Reinstall does not affect user or application settings, it will not repair issue stemming from those settings being corrupt.
Solution

Performing a Repair Reinstall
1.Insert the Windows XP CD into the CD or DVD drive.
2.Configure your system to boot to the CD drive.
3.Restart the computer.
4.When the computer prompts Press any key to boot from CD, press the (Spacebar).
5.The Welcome to Setup screen appears.
6.Press the (Enter) key to continue.
7.The system scans to see which hard drives are available.
8.When the license agreement screen appears, press the (F8) key to accept the license agreement.
9. You should now see: (C:\Windows )
Press F3 to quit, R to repair, ECS not to repair.
You want to press R at this point.
Windows will begin to load some files...asking you to please wait.
10.Setup will proceed with the installation sequence appropriate to the version of Windows XP being repaired.
Once setup is complete, the system will restart.
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