Well, firstly, sorry about the multitude of threads and their respective lengths,
I figured keeping everyone here in touch with my advantages and findings,
is a form of contribution to the issue, but take your time to read it, or just read the parts that are relevant and up to date.

So far I've found that :


  • Changing perms of the Tiledatalayer\Database folder, disables the Start button and apps like taskmanager on the next bootup, for the current user as well as every other account.
  • Copying and pasting that folder into the corresponding directory of another user, results in the same inconvenient errors.
  • When you boot once in Safe Mode (on your admin account or just another account) and then reboot and login on that account, the errors are gone for every account except the one you made the folder changes to, if you login on that account again, the errors infect the others again, therefore delete it in UAC

=> Conclusion : I prefer not to meddle anymore with the Tiledatalayer\database folder, where the tile arrangement is presumed to be stored in.


  • Using the Export-StartLayout cmdlet to create a LayoutModification.xml file and then place this in the hidden Default (user) folder, in AppData\Local\Microsoft\Windows\Shell , will set the StartLayout for any NEWLY CREATED account.


=> Conclusion : This works but you'll have to recreate and reconfigure all the other users again from scratch, it's not efficient or elegant, but works...


  • Using gpedit.msc (Group Policy Editor) isn't an option in the normal (this time, free) Windows 10 Home Edition.
  • Anything that gpedit.msc does can be done in the Registry as well (regedit.exe), the Group Policy Registry Refence (as you can find in my references area beneath) tells us what gpedit does to the registry, which keys and values it adds or changes. For our purposes (changing the StartLayout in GPE) :


HKLM\Software\Policies\Microsoft\Windows\Explorer!LockedStartLayout
HKLM\Software\Policies\Microsoft\Windows\Explorer
HKLM\Software\Policies\Microsoft\Windows\Explorer!StartLayoutFile


For a specific user change HKLM into HKU\[user SID] , both the key and the values have to be created, the first value is a DWORD, the second just a String, in which you put the path to your LayoutModification.xml file, in my case : C:\temp\LayoutModification.xml .


  • I set the C:\temp folder to SHARE (all perms to every user), thus everyone has the same privileges in handling this file, and everyone can access it. (lx07, this is what you meant, right, a shared folder that every user can access and has equal perms on, or is it something else)


=> Problem : Though I did all the previous, no changes occur in the StartLayout of the other users, it doesn't seem to do anything, yet according to the Reference (windows 10) and technet (windows 8) it should do what GPE does.

=> Conclusion : For now I can just recreate the accounts with the default one, and reconfigure them semi-automatically (using the StartLayout before creation, then using Themes, scripts,...), but I do want to know how to set a StartLayout file for Existing Users, like indicated in GPE.

=> Question : Does anyone know; what else I should do to get the Registry tweaks to work, or why they don't seem to work?

Thanks for your concern,

Kind Regards

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REFERENCES

group policy - Alternative to gpedit.msc for Windows Home editions? - Super User
Download Group Policy Settings Reference for Windows and Windows Server from Official Microsoft Download Center
Customize Windows 8.1 Start Screens by Using Group Policy
Customize Windows 10 Start with Group Policy (Windows)