Creative drivers can be a little "touchy" at times to get them in and see them made active by Windows. The first step is to go into the device manager and scroll down to the "Sound, Video, and Game COntrollers" section and open that up. You should see the single Creative X-FI(WDM) item listed aling with the usual Windows default items. Right click on that and choose the update driver option for a fresh try.
If updating the drivers through the DM fails to see results a total uninstall of everything would be the next step. That means drivers as well as the Creative sound mixer, EAX console, speaker settings, etc. for the alternative that seems to always work as the last resort. With everything removed you reboot the system to first see if Windows detects a new device. If not you now use the new hardware wizard to manually not automatically install the card by choosing the type of device from a list and proceed to browse for the drivers in the audio\drivers folder on the installation cd.
Once the main driver is highlighted and detected by Windows the needed drivers will then be copied and installed by Windows there making them active. If either of the two methods fail to see results you are more likely then to have received a bad card. The two methods do take some time but have been used here on different models to get sound working.
