I couldn't connect to Windows Update nor install .NET so I've done a clean install of Windows 8.1 from Microsoft's iso.
The same problem occurs : the loading bar is never beginning ! No error message.
I've compared what is happening on my Win 7 netbook with Wireshark. When searching for updates, it's sending http requests to Microsoft with a URL like /v11/2/microsoftupdate/. The fresh install of Win 8.1 basically doesn't try to connect anywhere.
I have no proxy, no firewall, no special configuration. Both laptops are on the same network.
Best Answer
Stop the
Windows UpdateService (via services.msc or in a cmd.exe which is started as admin vianet stop wuauserv- this improves speed of installing the MSU update which you have to download), download and install this update by double click on the MSU:Installing and searching for updates is slow and high CPU usage occurs in Windows 8.1
If the hack to stop Wu service doesn't speedup install of the MSU, extract the MSU with 7-zip and use DISM to install the update.
This skips the check if the update is required and works around the hang at "Searching for updates on this computer" while installing a MSU.
Do a reboot and check again for new updates. Now Windows Update will work and show new updates in a few minutes.