thanks to you....
but unfortunately I did what you said and I follow the instructions .
also the result of cleaning it was sucssesfull
.... but the problem is still staying....!!!
I may be need to format my pc.
If you say that the problem began when you installed an antivirus program, maybe it is blocking cs5 from connecting to the adobe servers via a firewall. Make sure the cs5 installation has access through the firewall.