Since you’re on a Windows Insider build and it started after an update, this is most likely not a Media Feature Pack issue. And is often improved in the very next update, you may wait till a new version is released or try the following:
- Install the latest Insider update (often fixed in the next patch).
- If no fix, roll back the recent update: Settings > Windows Update > Update history > Uninstall updates
- Go to WhatsApp App settings > Repair → Reset
- Reinstall WhatsApp from Microsoft Store
Workaround: Use WhatsApp Web until a patched build is released.
Since this is a user-to-user support forum, no one here has access to your system or can investigate Insider build issues directly. Raising this via Feedback Hub is the proper channel for Microsoft engineers to review and track such problems.
- Press "Win + F" to open Feedback Hub
- Click Report a problem
- Category: Apps > Other apps
- Describe: “WhatsApp Desktop stuck on loading screen after Insider update”
- Reproduce the issue and attach any screenshot/recording to the ticket, then submit it
Hope this helps. Feel free to update here if anything comes up!
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