Removing Real Player has removed your soundfile associations..such as your Windows actions files
they are wave files
open My Computer/Tools/Folder Options/File types
scroll down to any files such as Wav..Midi..Mpegs..or anything you see associated with Real Audio or Real player... click on it and If it says opens with RealPlayer click on change it . and in recommended programms you should see Windows Media Player..Quicktime or any other sound plugins you may have loaded
select Windows Media Player or any other you may have....