Sounds like something really wacky going on. Have you scanned for any viruses/pests/and such? What scanning programs are you using? Are they up to date?
last couple months,when trying to update or add almost anything,Im told that windows me disc is needed ,a different missing file everytime..99%of time if I search for file ,,it pops right up ,right where its suposed to be..(except my printer=missing cab file...
if I paste the path.a different 'missing file is brought up in same manner..and so on