Bizarre web connectivity issues?
First post here. I’ve run out of successful avenues for self-help, so hoping someone may have some insight into my bizarre issue. I’m moderately tech-savvy, but may lose you if things become too technical.
Several months ago, I built a new PC. It has been extremely stable and fast, but I have consistently had issues with certain websites. However, these problems often seem to RESOLVE when I utilize my work VPN. Three examples of the issue are:
– Dropbox will not sync / upload new files.
– Youtube will not initiate video uploads.
– When I try to connect to my work Outlook 365 webmail, it times out.
I do not have this problem on any other device connected to my network. I also did not have this problem with my previous computer that was directly connected to the router.
Windows 10 64-bit
Direct ethernet connection
Zyxel VMG4381 router (crappy, but required by my ISP)
Kaspersky Internet Security
Problem occurs in several browsers (Chrome, Firefox, IE, Edge). Problem occurs when I disable Kaspersky. Problem persists on different user accounts on the same computer.
Have tried all the usual fixes – firmware and software upgrades, clearing cache / cookies, hard reset of router, etc. I tried several different DNS server addresses and TCP/IP reset. Read online that someone had a similar problem resulting from their memory, but my chips pass a memtest.
The fact that it works with the VPN enabled makes me believe that this is somehow related to how my PC is routing OUT information. Furthermore, since most sites load normally but my problems seem to occur with Outlook365, Dropbox, and Youtube, I wonder if it specifically has to do with encrypted traffic. I don’t think that the issue is with the router or the firewall, since the problem is not replicated on other network devices and the problem is not resolved by disabling the firewall.
Has anyone heard of such a thing or have any clue as to the source of this problem? I’m at a loss.
Your help is deeply appreciated.