My Creative sound card (Vibra 128) stopped functioning

There's no sound from my PC, so I checked the
Device Manager, under the sound card properties's
Settings tab, there's only a message that
states:''You do not have sufficient security
privileges to change device properties. Please
contact your site administrator, or logout and log
in again as an administrator and try again''.
But I'm using Win ME and I'm the only user.
And I checked the Control Panel, under Sounds and
Multimedia Properties's Devices tab's Audio
Devices properties's, the Status states:''Driver is
enabled but inactive due to unknown problem''.
Removing and installing the driver doesn't help.

As I installed the new driver, SBPCI_WebDrvsV5_12_01.exe as suggested by Creative and restarted the PC, the PC stated that the ''ksuser.dll'' and the ''stream.sys'' were not found.
So I installed the two files from Windows System's folder itself. But after the whole installation was completed ''correctly'', the same old problem still persist.

Please help! =P