I've noticed that over time there are multiple entries for the same
ActiveX control listed in Internet Options -> Programs -> Manage Add-Ons
when selecting "Add-ons that have been used by Internet Explorer". For
example, I now have 2 entries for "Microsoft Terminal Services Client
Control (redist)" which lists mstscax.dll for the control.

I know that some add-ons use the same file but for different
functionality or methods from them but this one seems to be a pure
duplicate. I already went to the Add/Remove Programs applet and
uninstalled the Terminal Services Web Client but both these entries
remain.

I want to get rid of them so I can see what the client would see when
they visit a host that is running IIS with TSWEB added (Remote Desktop
Web Connection). That lets them remote into the host using a web
browser in case they are on a host where RDC (Remote Desktop Client)
isn't available and they cannot install it (but they may be able to
install the AX control). I want to see what prompts they would get,
like telling them to install the Remote Desktop Connection Web Client
(and ActiveX control). But it's already on my test host so I can't see
the process the client would go through.

I found several registry entries (and more than just 2 of them; 5 CLSID
entries are for it) that list the %systemroot%\system32\mstscax.dll file
as the InProcServer32 entry and the key is named "Microsoft Terminal
Services Client Control (redist)" but digging into the registry to
delete references to this AX control could end up with a corrupted setup
for IE. I could try deregistering the file using regsvr32.exe -u but
that isn't really an uninstall of the AX control but merely erasing the
pointer in the registry to it. Be great is there were a more elegant
method of wiping this AX control. But then maybe it's part of the RDC
(Remote Desktop Client) that is installed in Windows XP Pro to provide
that client - but why list its AX control *twice* in the add-ons for IE?

Follow these steps to remove an ActiveX controll:

1. Open 'Start Menu-->All Programs-->Accessories-->System Tools-->Disk Cleanup'.
2. Highlight "Downloaded Program Files" then click the "View Files" button.
3. In the opened window, right-click on the item that you wish to delete and select "Remove".


ju.c


"VanguardLH" <(E-Mail Removed)> wrote in message news:ggit5b$fc3$(E-Mail Removed)...
> I've noticed that over time there are multiple entries for the same
> ActiveX control listed in Internet Options -> Programs -> Manage Add-Ons
> when selecting "Add-ons that have been used by Internet Explorer". For
> example, I now have 2 entries for "Microsoft Terminal Services Client
> Control (redist)" which lists mstscax.dll for the control.
>
> I know that some add-ons use the same file but for different
> functionality or methods from them but this one seems to be a pure
> duplicate. I already went to the Add/Remove Programs applet and
> uninstalled the Terminal Services Web Client but both these entries
> remain.
>
> I want to get rid of them so I can see what the client would see when
> they visit a host that is running IIS with TSWEB added (Remote Desktop
> Web Connection). That lets them remote into the host using a web
> browser in case they are on a host where RDC (Remote Desktop Client)
> isn't available and they cannot install it (but they may be able to
> install the AX control). I want to see what prompts they would get,
> like telling them to install the Remote Desktop Connection Web Client
> (and ActiveX control). But it's already on my test host so I can't see
> the process the client would go through.
>
> I found several registry entries (and more than just 2 of them; 5 CLSID
> entries are for it) that list the %systemroot%\system32\mstscax.dll file
> as the InProcServer32 entry and the key is named "Microsoft Terminal
> Services Client Control (redist)" but digging into the registry to
> delete references to this AX control could end up with a corrupted setup
> for IE. I could try deregistering the file using regsvr32.exe -u but
> that isn't really an uninstall of the AX control but merely erasing the
> pointer in the registry to it. Be great is there were a more elegant
> method of wiping this AX control. But then maybe it's part of the RDC
> (Remote Desktop Client) that is installed in Windows XP Pro to provide
> that client - but why list its AX control *twice* in the add-ons for IE?

ju.c wrote:

> "VanguardLH" <(E-Mail Removed)> wrote in message news:ggit5b$fc3$(E-Mail Removed)...
>> I've noticed that over time there are multiple entries for the same
>> ActiveX control listed in Internet Options -> Programs -> Manage Add-Ons
>> when selecting "Add-ons that have been used by Internet Explorer". For
>> example, I now have 2 entries for "Microsoft Terminal Services Client
>> Control (redist)" which lists mstscax.dll for the control.
>>
>> I know that some add-ons use the same file but for different
>> functionality or methods from them but this one seems to be a pure
>> duplicate. I already went to the Add/Remove Programs applet and
>> uninstalled the Terminal Services Web Client but both these entries
>> remain.
>>
>> I want to get rid of them so I can see what the client would see when
>> they visit a host that is running IIS with TSWEB added (Remote Desktop
>> Web Connection). That lets them remote into the host using a web
>> browser in case they are on a host where RDC (Remote Desktop Client)
>> isn't available and they cannot install it (but they may be able to
>> install the AX control). I want to see what prompts they would get,
>> like telling them to install the Remote Desktop Connection Web Client
>> (and ActiveX control). But it's already on my test host so I can't see
>> the process the client would go through.
>>
>> I found several registry entries (and more than just 2 of them; 5 CLSID
>> entries are for it) that list the %systemroot%\system32\mstscax.dll file
>> as the InProcServer32 entry and the key is named "Microsoft Terminal
>> Services Client Control (redist)" but digging into the registry to
>> delete references to this AX control could end up with a corrupted setup
>> for IE. I could try deregistering the file using regsvr32.exe -u but
>> that isn't really an uninstall of the AX control but merely erasing the
>> pointer in the registry to it. Be great is there were a more elegant
>> method of wiping this AX control. But then maybe it's part of the RDC
>> (Remote Desktop Client) that is installed in Windows XP Pro to provide
>> that client - but why list its AX control *twice* in the add-ons for IE?

> Follow these steps to remove an ActiveX controll:
>
> 1. Open 'Start Menu-->All Programs-->Accessories-->System Tools-->Disk Cleanup'.
> 2. Highlight "Downloaded Program Files" then click the "View Files" button.
> 3. In the opened window, right-click on the item that you wish to delete and select "Remove".
>

The "Downloaded Program Files", when selected in Internet Options ->
Programs -> Manage Add-ons, will let you click the Delete key to get rid
of those programs (and which are stored under C:\WINDOWS\Downloaded
Program Files). What I was looking for is references to the prior used
AX control in the "Add-ons that have been used by Internet Explorer".

That there are multiple entries for the same file, in this case, means
it is likely that there are or were multiple class IDs for the same
control. I cannot use the Remote Desktop Web Connection method to
hookup to another host using a web server on that other host unless I
have these previously used AX controls enabled, but there are 2 of them
listed and I'm not sure which is needed or if both are needed (since
they point at the same mstscax.dll file). Yet there are 5 class IDs for
the same mstscax.dll file and I don't which of those go which of the 2
entries in the add-ons listing in IE.

In a clean install of Windows XP Pro, and after applying SP-3 and
subsequent updates, but before ever connecting to an IIS web server
which has TSWEB added (Terminal Services Web Connection), mstscax.dll is
not listed even once in IE's add-ons for those that have been previously
used by IE. Not only is this a list of previously used controls (some
of which are AX controls) but also whether they are enabled or not for
reuse. I suspect if I got rid of those registry entries matching up
with these previously used AX controls (which can be enabled or disabled
for status regarding reuse) that I might engender a prompt that I've
seen before in this RDP-web setup. I'm not positive but then I'd still
like to know how to clean up this prior-used control list for multiple
entries. I haven't found from where IE compiles this list. I've used a
couple Nirsoft utilities but they didn't list these particular
duplicated entries.

I'm not even sure how an add-on gets disabled. Maybe they use the
killbits to disable a control. If so, I could enable one of the
duplicated entries and see which one had its killbit removed, and repeat
for the other entry. Then I could see which CLSIDs in the registry were
associated with which entry in IE's add-on list. I could then check
interdependencies on that class ID to see how I might clean up the list.
I'll ponder over this and read http://support.microsoft.com/kb/240797
tomorrow. My eyeballs are itchy so it's time for bed.

VanguardLH wrote:

> ju.c wrote:
>
>> "VanguardLH" <(E-Mail Removed)> wrote in message news:ggit5b$fc3$(E-Mail Removed)...
>>> I've noticed that over time there are multiple entries for the same
>>> ActiveX control listed in Internet Options -> Programs -> Manage Add-Ons
>>> when selecting "Add-ons that have been used by Internet Explorer". For
>>> example, I now have 2 entries for "Microsoft Terminal Services Client
>>> Control (redist)" which lists mstscax.dll for the control.
>>>
>>> I know that some add-ons use the same file but for different
>>> functionality or methods from them but this one seems to be a pure
>>> duplicate. I already went to the Add/Remove Programs applet and
>>> uninstalled the Terminal Services Web Client but both these entries
>>> remain.
>>>
>>> I want to get rid of them so I can see what the client would see when
>>> they visit a host that is running IIS with TSWEB added (Remote Desktop
>>> Web Connection). That lets them remote into the host using a web
>>> browser in case they are on a host where RDC (Remote Desktop Client)
>>> isn't available and they cannot install it (but they may be able to
>>> install the AX control). I want to see what prompts they would get,
>>> like telling them to install the Remote Desktop Connection Web Client
>>> (and ActiveX control). But it's already on my test host so I can't see
>>> the process the client would go through.
>>>
>>> I found several registry entries (and more than just 2 of them; 5 CLSID
>>> entries are for it) that list the %systemroot%\system32\mstscax.dll file
>>> as the InProcServer32 entry and the key is named "Microsoft Terminal
>>> Services Client Control (redist)" but digging into the registry to
>>> delete references to this AX control could end up with a corrupted setup
>>> for IE. I could try deregistering the file using regsvr32.exe -u but
>>> that isn't really an uninstall of the AX control but merely erasing the
>>> pointer in the registry to it. Be great is there were a more elegant
>>> method of wiping this AX control. But then maybe it's part of the RDC
>>> (Remote Desktop Client) that is installed in Windows XP Pro to provide
>>> that client - but why list its AX control *twice* in the add-ons for IE?
>
>> Follow these steps to remove an ActiveX controll:
>>
>> 1. Open 'Start Menu-->All Programs-->Accessories-->System Tools-->Disk Cleanup'.
>> 2. Highlight "Downloaded Program Files" then click the "View Files" button.
>> 3. In the opened window, right-click on the item that you wish to delete and select "Remove".
>>
>
> The "Downloaded Program Files", when selected in Internet Options ->
> Programs -> Manage Add-ons, will let you click the Delete key to get rid
> of those programs (and which are stored under C:\WINDOWS\Downloaded
> Program Files). What I was looking for is references to the prior used
> AX control in the "Add-ons that have been used by Internet Explorer".
>
> That there are multiple entries for the same file, in this case, means
> it is likely that there are or were multiple class IDs for the same
> control. I cannot use the Remote Desktop Web Connection method to
> hookup to another host using a web server on that other host unless I
> have these previously used AX controls enabled, but there are 2 of them
> listed and I'm not sure which is needed or if both are needed (since
> they point at the same mstscax.dll file). Yet there are 5 class IDs for
> the same mstscax.dll file and I don't which of those go which of the 2
> entries in the add-ons listing in IE.
>
> In a clean install of Windows XP Pro, and after applying SP-3 and
> subsequent updates, but before ever connecting to an IIS web server
> which has TSWEB added (Terminal Services Web Connection), mstscax.dll is
> not listed even once in IE's add-ons for those that have been previously
> used by IE. Not only is this a list of previously used controls (some
> of which are AX controls) but also whether they are enabled or not for
> reuse. I suspect if I got rid of those registry entries matching up
> with these previously used AX controls (which can be enabled or disabled
> for status regarding reuse) that I might engender a prompt that I've
> seen before in this RDP-web setup. I'm not positive but then I'd still
> like to know how to clean up this prior-used control list for multiple
> entries. I haven't found from where IE compiles this list. I've used a
> couple Nirsoft utilities but they didn't list these particular
> duplicated entries.
>
> I'm not even sure how an add-on gets disabled. Maybe they use the
> killbits to disable a control. If so, I could enable one of the
> duplicated entries and see which one had its killbit removed, and repeat
> for the other entry. Then I could see which CLSIDs in the registry were
> associated with which entry in IE's add-on list. I could then check
> interdependencies on that class ID to see how I might clean up the list.
> I'll ponder over this and read http://support.microsoft.com/kb/240797
> tomorrow. My eyeballs are itchy so it's time for bed.

Nope, that was the wrong KB article because killbits is not how an
add-on is marked Disabled for IE.

To figure it out, I used Installwatch Pro (free) to take a snapshot of
the system, including the registry, while the duplicated add-on was
enabled, changed them to disabled, and analyzed the changes. Then I
took another snapshot while the add-ons were disabled, changed them to
enabled, and analyzed the changes. I could then see the registry key
getting touched was:

HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Ext\Settings

The CLSID for the disabled control would get added under this registry
key to add a data item "Flags" with value 1 (apparently that means to
enabled the "disable" flag on the control identified by its CLSID).
Once I knew the registry key, I could search Microsoft's support KB site
to find http://support.microsoft.com/kb/883256.

When I disable the duplicate "Microsoft Terminal Services Client Control
(redist)" controls in IE's add-on list, they show up under this registry
key. When I disable them, they disappear. Yet there are 3 more CLSID
entries for this same mstscax.dll that are shown under this registry key
but which are not listed in IE's add-on list (as disabled). I'll have
all the add-ons in IE's list enabled so nothing should be under this
registry key but there are 3 CLSID entries there for that file. So when
I disable the 2 that I can see in IE's add-on list and the 3 that are
not in that list but other CLSID entries for that mstscax.dll file,
there's the 5 CLSIDs that I found before for this file.

Plus there is another CLSID under the Ext\Settings registry key for a
disabled add-on but for which there is no CLSID registry key to define
it. {9030D464-4C02-4ABF-8ECC-5164760863C6} is listed under the
Ext\Settings registry key for a disable add-on for Windows Live Sign-in
Helper (http://www.castlecops.com/tk29963-Wi...Login_dll.html). I
had that installed once when I trialed Windows Live Mail (to provide
Deltasync protocol access to my free Windows Live Hotmail account) but
that was some of the included Live fluff that I immediately used
Add/Remove Programs to uinstall after installing WLM yet this was a
remnant left behind after the uninstall. Since I won't be installing it
again, I don't need a Disable waiting in the Ext\Settings key to disable
it as soon at it gets installed, so this gets deleted from the registry.