Help connection issue

[knauszi]

Hi, I experience a special connection problem with my GT-P6210. It connects to wifi, and most websites are loading fine in browsers. At a lot of other sites, including very safe ones, like Google, however, I got one or more security warning, before they load. Android apps, like Facebook and Android Market, don't connect at all. I guess, this issue has to do something with the https protocol. I removed my antivir program, but it didn't help. It is a new issue, I have used my tablet for years without problems like this. I'd be thankful for any idea.