All Windows Store apps report "The parameter is incorrect"

imrazor · 24 Apr 2018

It all began when I was trying to get Firefox to open a downloaded Word .doc file. Firefox absolutely refused to realize that I had Word installed. So I did what I usually do when Firefox is obstinate about opening a file; I tried to locate Winword.exe and manually associate it with .doc files. Except I couldn't find Winword.exe anywhere.

I finally found it in a folder I had never seen before, "C:\Program Files\Windowsapps". The problem was that the folder was hidden and had some very strange permissions on it. So I took ownership of the folder and all subfolders and gave myself full control. That was a mistake.

Now when I open *any* Windows Store/Metro app I get the message "The parameter is incorrect". How can I repair the permissions on "C:\ProgramFiles\WIndowsapps"? I've already given ownership back to "TrustedInstaller", but I'm still getting "The parameter is incorrect." I also tried "sfc /scannow" but that didn't help.

BTW, all "classic" desktop apps work fine and Windows boots without any issue. But Office365 is totally hosed...

All Windows Store apps report "The parameter is incorrect"-2018-04-24.png

EdTittel · 25 Apr 2018

Can't really find much useful about this precise problem. But attacking it via problem analysis, here's what I'd do myself, if faced with this issue, in 3 phases

Phase 1: Run the Windows Store Apps Troubleshooter (TF Tutorial)

If that doesn't work, onto Phase 2:

Phase 2: Uninstall all store apps, then re-install and re-register them
1. Uninstall all store apps with this command from an administrative PowerShell session

Code:

Get-AppxPackage -AllUsers | Remove-AppxPackage

2. Reinstall and Re-register Store apps (TF Tutorial)

If that doesn't work, onto Phase 3:

Phase 3: Perform an in-place upgrade repair install of Windows 10 (TF Tutorial)

HTH, and best of luck in getting this fixed.
--Ed--

imrazor · 25 Apr 2018

I tried everything up to Phase 3. Before nuking my entire install of Windows, I decided to try reinstalling Office. That worked - for my Office apps. Word, Excel, etc. all start fine now. However, all the other Metro apps remain hosed.

Given that re-installing Office (from the MS installer) fixed the problem, are there any other tricks before I take the drastic step of re-installing Windows? None of the Powershell commands seemed to work...

EdTittel · 26 Apr 2018

An in-place upgrade repair install isn't quite a clean install. That said, it leaves apps and applications alone. But because you uninstalled all the UWP stuff using PowerShell, I'm hopeful it will put things back the way they should be. This process only takes 15 minutes or so, so you'll know pretty quickly if it helps or not. Only if it fails does a clean install come into the picture. Here's a link to that tutorial again: Repair Install Windows 10 with an In-place Upgrade.
HTH,
--Ed--

imrazor · 26 Apr 2018

Thanks it worked. I was worried about losing several hundred gigabytes of downloaded games, but all I had to was rerun the launcher. I also had to reinstall some drivers, which was a little surprising. I've also lost some OEM software; is there any way to get that back?

Otherwise, Windows Store and Office 365 all appear to be working now. Thanks.

EdTittel · 27 Apr 2018

Glad you got it (mostly) sorted. As for the OEM stuff, you'll probably have to find it, download it and reinstall it. If you can't remember, you may be able to mount your backup and explore its contents and get the info you need from there. Hope it all goes well.
Best wishes,
--Ed--

DexEze · 27 Oct 2019

I found how to fix this issue without an in-place upgrade repair install of Windows 10.

Instructions:

1. Open Command Prompt in Administrator mode. You can do this by typing in your search bar cmd and then ctrl + shift + enter.
2. In command prompt type: icacls "C:\Program Files\WindowsApps" /q /c /t /reset

Of course if you're having issues with the WindowsApps folder on a different drive or a different folder location adjust that accordingly.

This should fix the issues.

Note that this is a fix for if you have changed the permissions for the WindowsApps folder and cannot open Microsoft Store or some Apps contained within said folder on Windows 10. It fixes the issues by restoring the permissions to default.