After months of trying every network reset, regedit etc. , I have a solution that works for me and I haven't seen this solution posted.
Someone correctly said WinHTTP Web Proxy service wasn't starting, and said change the value to 3 via regedit to start it.
The solutuion did not work for me (as my value was already 3) although I shared the same issue that WinHTTP wasn't starting.
With the latest 24H2, apparently the service "DNS Client" has not become a dependency, prior to this release, only "DHCP Client" was a dependency.
On my PC, prior to upgrade, I noticed DNS Client was not started and greyed out. Changing the Start value in the registry from 4 to 3 addresses "DNS Client" starting (after a reboot).
Once this is resolved so that DNS Client is started, the upgrade to 24H2 worked first time; WinHTTP starts ok when the two dependencies start ok i.e. DNS Client and DHCP Client are started ok.
Hope this helps - this issue has been a severe pain for me and others with a simple fix!