If you’ve noticed Windows Update hang at 0% while downloading the new Windows 10 Insider build, try this to accelerate the download progress.
Fix Windows Update Stuck while downloading the build 10158/10159
1. Open Run command and type Services.msc, find ‘Windows Update’ service, and stop it.
2. Navigate to ‘C:\Windows\SoftwareDistribution\Download’ folder and delete all the downloaded updates,
3. Restart the Windows Update service in Services console.
Note: If you don’t want to delete the Download folder contents, try to stop and restart the Windows Update service and see it works.