We will be retiring the CDN used by earlier versions of WinGet.

Please upgrade to WinGet 1.6 or WinGet 1.7-preview (or later as new releases come out).

You can update "App Installer" via the Microsoft Store.
You can also use https://aka.ms/getwinget to install the latest available stable version.
For preview builds, you can use https://aka.ms/getwingetpreview.

Note: The default behavior on a new Windows installation is to have the Microsoft Store check for updates and to install the latest version of WinGet. This should affect less than 2% of devices. WinGet can be updated by updating the App Installer in the Microsoft Store. It is also possible to run winget install "App Installer" -s msstore --force via the command-line.

New Windows installs (Azure Virtual Desktop for example) may have an earlier version of WinGet (delivered via App Installer) and they may not function correctly to download the default "winget" source. Updating the client to the latest version via the Microsoft Store, or GitHub will mitigate the issue.

Several users have reported issues with getting source updates to function after installing the latest version of WinGet. We're looking into the root cause.

If you run winget source update --force in an administrator terminal/shell it should resolve the issue.
If that doesn't work, try powershell -command Add-AppxPackage https://cdn.winget.microsoft.com/cache/source.msix

Latest Update:
CDN Migration is complete