3 similar solutions below to try:

1. Start > Run, type "regedit" (without quotes) in the Open box, and then click OK.
2. In Registry Editor, locate and then click the subkey that is listed by the error message.
3. On the Edit menu, click Permissions.
4. Under Group or user names, click Everyone.
Note You must add the Everyone group if it is not available. To do this, follow these steps:
a. In the Permission for Office dialog box, click Add.
b. In the Select Users, Computers, or Groups dialog box, click Advanced.
c. In the Select Users, Computers, or Groups dialog box, click Find Now.
d. Under Name (RDN), click Everyone, and then click OK.
e. In the Select Users, Computers, or Groups dialog box, click OK.
5. Under Permissions for Everyone, click to select the Full Control check box.
6. Click OK.
7. Exit Registry Editor.
8. Run the Setup program for your Office program.

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1. Start > Run.
2. Type "regedit" (without the quotes) and click OK.
3. Browse to the specified registry key.
4. Right click the key and select "Permissions."
5. In the Group or User names field, select the user installing the program. Be sure the user has administrative rights.
6. Under the Permissions field, make sure "Full Control" and "Read" are both set to "Allow."
7. Click OK and attempt the operation again.

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1. Run regedit
2. Right click on HKEY_CLASSES_ROOT
3. Click Permissions
4. Click on the Add button then add Administrators and click OK.
5. In the resulting "Permissions for HKEY_CLASSES_ROOT" window, check the "Allow" box for full control and read.
6. Click the Add button again and add SYSTEM and again check the Allow box for full control and read.
7. Click Ok, exit regedit.
8. Rerun setup