For Windows Vista, the solution to getting a DLL or OCX file registered is to turn off User Account Control for the user profile attempting to do the installation.

To do this:

1. Click Windows Vista Start button (looks like the Windows log on top of a round ball at the bottom left side of your desktop)
2. Click Control Panel
3. Click Security (Or Security Center in Classic Control Panel View)
4. Click User Accounts in the left-hand pane.
5. When the User Accounts Window opens, click the text "User Accounts" at the top of the panel (next to the icon showing a couple of generic users)
6. Click the "Turn User Account Control on or off" link.
7. Uncheck the box next to "Use User Account Control (UAC) to help protect your computer.
8. Click "OK".

You will need to reboot your computer for this change to take effect.

When you get back into your computer, enter the following command from the Search box from the Programs Menu:

Regsvr32.exe C:\Windows\System32\NameofyourOCXorDLLFile.OCX

Where "NameofyourOCXorDLLFile.OCX" is the actual name and path to the OCX or DLL file you were having a problem with.

Press Enter.

You should recieve a message stating that the DLL or OCX file was correctly registered and you can now use your application.