Whenever I power Down or reboot the Realtech Sound Drivers disappear. I have to reinstall them after every restart. This is on my main workstation that I have built in the last few months so I haven't had much time to play with it to work out the issues.
Generally because the Realtech Sound Drivers are not Digitally Signed you can not reinstall or initially install them after you have contacted the M$ Update Server and allow your system to install the Initial Download from M$ that allows either Windows Update or Microsoft Update to be run on your system.
As I;m inherent ally LAZY I don't bother messing around I just make sure that I have an Up To Date Backup and then Blow the Boot Drive away with a Wiping Utility and rebuild from a Image of the HDD that I made after doing a Base install of the Hardware Drivers that I need and the Software that I use. I do have to reapply any updates that are made after that image was but it's just faster for me to do it that way.
Maybe one of the others here has some idea of what is happening here and can suggest a Registry Hack that may save you the need to reload. But once Windows starts to Screw Up like this I never fully trust it again so I find it easier to just start from a Known Good Point and rebuild completely. In the mean time I just have the Latest Realtech Sound Drivers copied to a Temp Folder on a Slave Drive and Update them on every Restart till I get the time to reload the System. I also make a Slipstreamed Install Disc for Windows with all my Hardware Drivers with nLite as this saves a lot of time and messing around when you need to rebuild from Scratch. I also setup nLite for a Unattended Install so it saves even more time and the need to enter a Product Code for Windows. You may like to try this at some time. :)
http://www.nliteos.com/download.html
Just make sure to read the User Guides on the nLite site as the first time you use it it appears different or strange but it's really straight forward.
http://www.nliteos.com/guides.html
OH BTW nLite only works up to XP if you want to do the same thing with Vista you can use vLite available here
http://www.vlite.net/download.html
Col