Unable to install Terminal Services ActiveX Control (mstscax.dll)

Hi

Have a problem in XP SP2, unable to install the terminal services activex control, so unable to connect to remote web workplace through the browser.

I initially found loads of spyware etc on the PC which I manually cleaned up.  I then installed AdAware & SpyBot afterwards to give it the final clear out.  The PC then went back to my client who the following day reported that he cannot get onto the remote web workplace anymore.

At the time it was on IE6.  Going into Manage AddOns in IE6 showed the control was there (mstscax.dll) but he could not get into the remote location he wanted.

I've looked at this, assumed it was a browser problem and tried to upgrade to IE7.  It wouldn't let me install it so I completed a repair install of XP to hopefully address the browser issue. It didn't work.
I then removed spybot and adaware and installed IE7 again which worked this time.  In the Manage AddOns, I selected the mstscax.dll entry and deleted it.  Now when you visit the rww site, it pops up a message saying you need to install the terminal services activex control and pops up the yellow information bar below the address bar in IE7 asking me to install it.  I select "run" but it then just goes back to the previous page and will not install.  I have tried regsvr and regsvr -u on the dll which makes no difference.  No matter what I do, it will not allow me to reinstall this activex control.  Now in manage addons, it is not present.

After googling the problem, it seems as though the problem may be related to the installation of spybot, setting a killbit on the activex control so it could not be run.  I removed the associated registry entry suggested in a number of posts but it made no difference.  As a further kick in the teeth, because of the repair install I cannot use System Restore anymore to go back to prior to the installation of SpyBot - wish I had realised it may be SpyBot related before i carried out the repair install.

I've tried reinstalling SpyBot, both 1.4 and 1.52 - they both come up with registry access errors when trying to install.  1.4 doesn't function at all, but 1.52 does.  I have updated then immunized all, then undone all the immunizations but it doesn't work.

Any clues where abouts the needle may be in this haystack? Client desperate to avoid wiping this pc and rebuilding afresh due to some of the software installations he cannot replace.

Thanks for any help on this one.
eMicros