Driver access problem after KB890830 and KB890175

I have some applications depending upon a private driver
running on Windows XP Home Edition fully updated. The
driver is properly installed to Windows\System32\Drivers.
Until now I have had no problems with this.

After I successfully installed KB890830 (Malicious
Software removal tool) and KB890175 (Security Hotfix)
I suddenly experience a rather peculiar situation: My
applications fail to establish contact with the driver
when I run as a limited user.

Running one of my applications while logged on as
administrator works fine, the same if I as limited user
run an application with "run as" and identifiy the
administrator.

Once I have run an application while logged on as a
limited user but with "run as" administrator then I can
run this application as limited user with no problem
until next time I have been logged off and log on again.

In fact if I correctly remember the few tests I have done
so far I can run ANY of my applications as limited user
once I have run (at least) one of them with "run as"
administrator.

Now, my applications are used by customers that should
be able to do so without being logged on as administrator
so this new behaviour in Windows XP is rather disturbing.

Anybody having information or suggestions would be
very welcome!

regards Sven

Some additional information (I did a little testing):

The applications are designed to be available to any
logged on user on the computer, even to "Guest".

As it is now the first time one of the applications
is started this must be done with administrator privileges
but once a limited user has run one of the applications
with "run as" administrator ANY logged on user can
run ANY of my applications with no driver problem
until the computer is rebooted.

Limited user logoff and logon does not disturb operations.

Hoping for information

Sven


"Sven Pran" <> wrote in message
news:xi9Gd.4616$...
>I have some applications depending upon a private driver
> running on Windows XP Home Edition fully updated. The
> driver is properly installed to Windows\System32\Drivers.
> Until now I have had no problems with this.
>
> After I successfully installed KB890830 (Malicious
> Software removal tool) and KB890175 (Security Hotfix)
> I suddenly experience a rather peculiar situation: My
> applications fail to establish contact with the driver
> when I run as a limited user.
>
> Running one of my applications while logged on as
> administrator works fine, the same if I as limited user
> run an application with "run as" and identifiy the
> administrator.
>
> Once I have run an application while logged on as a
> limited user but with "run as" administrator then I can
> run this application as limited user with no problem
> until next time I have been logged off and log on again.
>
> In fact if I correctly remember the few tests I have done
> so far I can run ANY of my applications as limited user
> once I have run (at least) one of them with "run as"
> administrator.
>
> Now, my applications are used by customers that should
> be able to do so without being logged on as administrator
> so this new behaviour in Windows XP is rather disturbing.
>
> Anybody having information or suggestions would be
> very welcome!
>
> regards Sven
>