(adsbygoogle = window.adsbygoogle || []).push({}); im on windows 7 and i cant do the first part which prob everyone can do and its driving me crazy please if anyone can help tell me where to find charles-proxy-ssl-proxying-certificate.crt and tell me exactly what to do cause windows 7 is so hard to understand thanks

Make a copy of charles-proxy-ssl-proxying-certificate.crt (C:\Program Files\Charles\doc) and rename it
to CA24.cer (Win7 users will have to enable "show file extensions")

where the hell is that ''show file extensions'' buttoncant find it