Registering a dll returns 0x80020009 error

regsvr32.exe needs to be run as an administrator. Maybe this was the cause?

For Windows Vista/Windows 7 users: Click Start>All Programs>Accessories, then right-click on “Command Prompt” and select “Run as Administrator” Type in the following command exactly as you see it and press ENTER. secedit /configure /cfg %windir%\inf\defltbase.inf /db defltbase.sdb /verbose Wait for the command to complete, it can take some time so please be patient. Once the command has completed, try to register a dll file again.