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Question

Correcting and/or Uninstalling/Installing Windows Installer

May 20, 2012 10:13PM PDT

I have a Dell E521 running Windows XP Media Center and for several weeks now I have not been able to install any programs/updates? Not so sure about the updates. I keep getting an error message that the installer cannot be accessed. I have tried setting a restore point to before this all happened but without success. This is due to using PC Pro Cleaner which sets its own restore point each time its used. I updated the installer to 4.5 this morning and tried installing MS Fixit Center again but without success. I tried adding an external hard drive to the computer but it did not install correctly as I cannot access the drive area on the dashboard of the hard drive. I'm not very tech savvy so I am concerned about following suggestions not knowing if I'm doing it correctly. Can you provide the best solution to this problem and how I can resolve this issue quickly. I was also thinking of reinstalling windows but not sure if this should be done and how.

Discussion is locked

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Answer
The moderators have seen registry cleaners
May 21, 2012 1:38AM PDT

Do so much damage that a full install has been required to get it all working again.

About the tech savvy part. Give yourself time to find Dell's XP install notes for your machine and while you do that, backup what you can't lose to more than one place or thing.
Bob

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hint
May 22, 2012 5:12PM PDT

Better solution for you.
First start the pc in safemode and start as Administrator not your account, okay!

after that, Click Start, and then click Run.

In the Open box, type cmd, and then click OK.

At the command prompt, type msiexec.exe /unregister, and then press ENTER.

Type msiexec /regserver, and then press ENTER.

Verify that the SYSTEM account has full control access permissions to the
HKEY_CLASSES_ROOT
hive in the Windows registry. In some cases, you may also have to add Administrator accounts. To do so:Important This section, method, or task contains steps that tell you how to modify the registry. However, serious problems might occur if you modify the registry incorrectly. Therefore, make sure that you follow these steps carefully. For added protection, back up the registry before you modify it. Then, you can restore the registry if a problem occurs. For more information about how to back up and restore the registry, click the following article number to view the article in the Microsoft Knowledge Base:
322756 How to back up and restore the registry in Windows

Click Start, click Run, type regedit in the Open box, and then click OK.

Click the following registry hive:
HKEY_CLASSES_ROOT

On the Edit menu, click Permissions.

If SYSTEM is not listed in the Group or user names list, click Add, make sure that the local computer name appears in the From this location box, type system in the Enter the object names to select box, click Check Names, and then click OK.

Click SYSTEM in the Group or user names list, and then select the Full Control check box under Allow in the Permissions for SYSTEM box.

Click Apply, click OK, and then quit Registry Editor.

Restart the computer.

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Answer
hint
May 22, 2012 5:13PM PDT

Better solution for you.
First start the pc in safemode and start as Administrator not your account, okay!

after that, Click Start, and then click Run.

In the Open box, type cmd, and then click OK.

At the command prompt, type msiexec.exe /unregister, and then press ENTER.

Type msiexec /regserver, and then press ENTER.

Verify that the SYSTEM account has full control access permissions to the
HKEY_CLASSES_ROOT
hive in the Windows registry. In some cases, you may also have to add Administrator accounts. To do so:Important This section, method, or task contains steps that tell you how to modify the registry. However, serious problems might occur if you modify the registry incorrectly. Therefore, make sure that you follow these steps carefully. For added protection, back up the registry before you modify it. Then, you can restore the registry if a problem occurs. For more information about how to back up and restore the registry, click the following article number to view the article in the Microsoft Knowledge Base:
322756 How to back up and restore the registry in Windows

Click Start, click Run, type regedit in the Open box, and then click OK.

Click the following registry hive:
HKEY_CLASSES_ROOT

On the Edit menu, click Permissions.

If SYSTEM is not listed in the Group or user names list, click Add, make sure that the local computer name appears in the From this location box, type system in the Enter the object names to select box, click Check Names, and then click OK.

Click SYSTEM in the Group or user names list, and then select the Full Control check box under Allow in the Permissions for SYSTEM box.

Click Apply, click OK, and then quit Registry Editor.

Restart the computer.