Error:

Error 1401: Could not create key “HKEY_USERS\S-1-5-21\Software\Classes”. Verify that you have sufficient access to that key.

Error Message:

Causes:

1. These errors all occur when the Windows Installer cannot successfully modify the registry.
2. These errors occur when the installer cannot create, read, or write the necessary entries.
3. This problem appears when you don’t have permission to required registry or if the registry entry is corrupted.
4. The logged on user may not have sufficient permission to install the software.

Solution 1:

1. Start > Run > type regedit
2. Navigate to path shown in error message “HKEY_USERS\S-1-5-21\Software\Classes”
3. Select that specific registry, right click and select “Permissions”
4. Give full control permission to EVERYONE & SYSTEM account
5. Click OK and Apply.

Solution 2:

Verify the Registry Permissions:

1. Click Start > Run
2. type regedit and then press Enter.
3. Select HKEY_CLASSES_ROOT, on the Edit menu, click Permissions.
4. Verify that the SYSTEM & EVERYONE account has been added and that it has Full control. If it does not, add the SYSTEM & EVERYONE account with Full control.
5. Please use the same method to give Full control permission to the following registry keys:                                                                                                         HKEY_CURRENT_USER                                                              HKEY_LOCAL_MACHINE