It's not enough to be an administrator. The batch file has to be 'Run as admin'.
Also, you may not have to register vfp6r.dll at all because it's on the Windows search path.
The vfp6renu.dll does not required registration at all.

>I have been using a simplified procedure to load the VFP6 runtime modules onto WinXP workstations.
>The following batch file is used:
>
>copy vfp*.* %windir%\system32
>%windir%\system32\regsvr32 %windir%\system32\vfp6r.dll /s
>%windir%\system32\regsvr32 %windir%\system32\vfp6renu.dll /s
>
>This has worked for serveral years under a Windows 2003 Server. It also worked when some workstation began to be set up as terminal servers.
>
>With a recent upgrade of the server to Windows 2008, problems arose. The network people report that terminal server sessions under Windows 2008 act as Vista computers. We now get an error running regsvr32 which reports:
>
>c:\windows\system32\vfp6r.dll will not load. (The program has been verifited as being in ..\system32\
>
>Is there something else required in a Vista environment for such a "simple" loading procedure to work?
>
>Yes, the person loading the software was an administrator.
>