Sadly there's nothing on your PCs to fix here. A Microsoft moderator confirmed in an earlier thread that this message is expected behavior, from stricter identity checks added to Quick Assist, and not a VPN or settings problem. Microsoft also no longer recommends Quick Assist for managed business devices, and points to Intune Remote Help instead.
If your devices are in Intune, this is the path:
- Check with your Intune admin that you have Remote Help licenses. It's an add-on to Intune Plan 1 or Plan 2, and both the helper and the person being helped need one.
- The admin turns Remote Help on for the tenant (it's off by default) and gives helpers the Remote Tasks - Offer remote assistance and Remote Assistance Connector - Read permissions.
- Deploy the Remote Help app to both PCs, then both of you sign in with your work accounts to start a session.
Are your PCs managed in Intune, or are they standalone business machines?
If this resolved your issue, please consider accepting it as the answer. If you aren't on Intune, let me know and I'll be happy to keep helping.
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