For the last few days, I just couldn’t connect to work VPN from my Windows 10 laptop. Rather, I could connect, and authenticate successfully, but as soon as I accessed anything, it would disconnect stating a tls-error, or decrypt-error. I tried numerous things – uninstalling VirtualBox, lowering MTUs to 1492, then to 1472, cleared out OpenVPN registry settings, tried Viscosity (which looks quite nice, and is very cheap – but not free). Nothing worked.
In the end, a simple reset of WinSock sorted it out. I opened up an admin command prompt, and ran the following:
netsh winsock reset catalog
In hindsight, I was playing around with socks proxies, and ssh tunneling to get into a dev private AWS subnet, but the issue was hard to trace down, and I hope this can help somebody else in the future.