lost icons

[clauded]

all the icons in my taskbar have plyed a disapearing on meat first some were missing at boot they next they would be backmthey more disapeared and now they are all gone except for msn mesenger and norton av,the icons for my scanner and adsl and sound volumeand evrything else i had there are gone yet all the utilities work,i can get to the internt and use the scanner,this started out about the time i pu service pack 2 on my windows xp pro,hope someon can help me out on this,i don`t think this a virus cause i scanned it all to death using norton panda online,house call adaware pro,hijack this and seach and destroy,and it came out cleanany help appreciated
ps sorry for the spelling but my finger can`t follow my head