We disable IPv6 often when troubleshooting a network issue. Nothing that I have seen requires IPv6, and turning it off solves more issues than we would expect even today. It’s not the first thing I’m going to try, but I’ll often do it if I have to reboot anyway.
I also uninstall Dell Optimizer and Dell Optimizer Service on sight regardless of the issue because that evil will cause problems eventually. Best to just eradicate it on sight.