Not able to unregister mxtscax.dll for Remote Desktop

Hello,

I am trying to update Remote Desktop on XP SP2 to v5.23790.2589 using
Msrpdcli.exe v6.0.2600.0. I have done this successfully on at least ten
systems and not had a problem. With this version I can set the registry to
redirect the default printer only on terminal server.

On this Dell Latitude D520, when I try to unregister mxtscax.dll using
regsvr32 /u mxtscax.dll, I get -

DllUnregisterServer in mstscax.dll failed.
Return Code 0x80070002

Any idea how I can get this dll unregistered?

Thanks.

I'm suffering similarly with the same error, an Installshield driver.

DllUnregisterServer in objps8.dll failed.
Return code was: 0x80070002

Another source suggected it was because the path length had too many
characters, but the path length short.

Any clues to resolve this issue welcome.