Hello AlainCh2,
The confusion stems from a misunderstanding of how Windows configuration works. "CSPs" (Configuration Service Providers) like ApplicationManagement/AllowAppStoreAutoUpdate are interfaces designed specifically for Mobile Device Management (MDM) servers such as Microsoft Intune, not for direct local editing. You cannot "open" a CSP editor on a standalone Windows machine. To modify the underlying setting locally, you must edit the Group Policy Object (GPO) or the Windows Registry, which maps directly to that CSP. The error you are seeing confirms that a restriction is active on the Microsoft Store update mechanism, which governs Phone Link.
To resolve the "App update policies on this PC are preventing you from receiving a required app update" error, you need to disable the restriction using the Local Group Policy Editor. Open gpedit.msc and navigate to Computer Configuration > Administrative Templates > Windows Components > Store. Look for the policy named Turn off Automatic Download and Install of updates. If this policy is set to Enabled, it effectively sets the CSP value to block updates. You must double-click it and set it to Disabled or Not Configured. This single policy controls the update mechanism for all Store applications, including Microsoft's own Phone Link and third-party software; there is no granular distinction between the two in this specific policy.
If you are on Windows Home edition or prefer the direct registry method (which is what the CSP actually modifies in the background), open regedit.exe and navigate to HKEY_LOCAL_MACHINE\SOFTWARE\Policies\Microsoft\WindowsStore. Look for a DWORD value named AutoDownload. If the value data is set to 2, updates are blocked. You should delete this AutoDownload value entirely, or change its data to 4 to force automatic updates on. You may also need to check HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\WindowsStore\WindowsUpdate and ensure AutoDownload is not set to 2 there either. A reboot is required for these changes to take effect.
I hope you've found something useful here. If it helps you get more insight into the issue, it's appreciated to accept the answer. Should you have more questions, feel free to leave a message. Have a nice day!
VP