D255 aspire 1 accer wifi problem

heyy buddy,

i m using my laptop accer d255 aspire one since three years. but last month i got my window starter corrupt. i reinstalled a same window starter but not genuine. currently my laptop is not connecting to a wifi. i also used trouble shooter but the result is always about wifi adapter problem which is not. the wifi adapter is working correctly . i dont know y it s not connecting. in the wifi icon there is a red cross . and it is showing no signals. i also used the FN button to turn on the wifi but it show no result.

ANATHOR MAIN PROBLEM IS THAT MY LAPTOP IS NOT ALLOWING TO INSTALLED A ANTIVIRUS . I RECENTLY INTSTALLED A KASPERKEY ANTI VIRUS IN THE USB BECOUSE THE INTERNET IS NOT WORKING BUT WHEN I OPENED THE FOLDER OF INSTALLED ANTIVIRUS IT SUDDENLY CLOSED THE FOLDER.

KINDLY GIVE ME THE SOLUTION THNKS