I recently did a fresh install when I switched from Kaspersky Total to Kaspersky plus.
Like I said, this has been the case for over a year when websites stopped working overnight and I thought it was my isp. I was using Total then.
No it isnt. However the crux remains, when I disable Kaspersky or add the sites to trusted, they all start working like a charm.
Tbh a perculiar thing I observed, of all the sites it facing this, torrents were the worst hit. Not one would open with Kaspersky enabled. If I disabled 'K' - Voila!
I even got a vpn subscription thinking it was my isp all this while.