Hey!
First of all, I want to thank you all for you concern and useful pieces of advice. Fortunately or not, I did not need to uninstall any programme - not even McAfeee Security Centre - and things seem to be back to normal again. Perhaps it sounds as mysterious as my post itself, but I really mean the problem is gone without any apparent reason - as it appeared. I was about to uninstall McAfee when I decided to do one last scanning. As it was running, the computer got frozen for some seconds and a message was displayed, informing me the scan had been finished. Then, Windows Live Messenger window opened by itself. As I logged in, the colours were in their appropriate place and the trouble I faced had merely vanished. Perhaps the believers may call it a miracle. I sincerely hope it doesn't happen again, and I reiterate my thanks to all of you.
See you around.
Mateus.
... pelo postigo de quem escreve
tudo - olhos, sóis, lentes -
na vigília, nas insônias
: o universo às escâncaras ...