Win10: App: Modern: Apps fail to start if default registry or file permission modified

I was doing chkdsk c: /f to fix crashing Xbox App. When my computer booted back up I have opened Event Viewer to see what, if anything, was fixed. Instead I had found the following error: Log Name: Application Source: Application Error Date: 1/31/2016 5:58:23 PM Event ID: 1000 Task Category: (100) Level: Error Keywords: Classic User: N/A Computer: Description: Faulting application name: backgroundTaskHost.exe, version: 10.0.11102.1000, time stamp: 0x569769f1 Faulting module name: twinapi.appcore.dll, version: 10.0.11102.1000, time stamp: 0x56976701 Exception code: 0xc000027b Fault offset: 0x000000000006b763 Faulting process id: 0x304 Faulting application start time: 0x01d15c93ee996bcb Faulting application path: C:\WINDOWS\system32\backgroundTaskHost.exe Faulting module path: C:\Windows\System32\twinapi.appcore.dll Report Id: 83dba75c-d113-4227-9bb5-5e25e3aeb400 Faulting package full name: Microsoft.People_10.0.3450.0_x64__8wekyb3d8bbwe Faulting package-relative application ID: x4c7a3b7dy2188y46d4ya362y19ac5a5805e5x Event Xml: 1000 2 100 0x80000000000000 6675 Application backgroundTaskHost.exe 10.0.11102.1000 569769f1 twinapi.appcore.dll 10.0.11102.1000 56976701 c000027b 000000000006b763 304 01d15c93ee996bcb C:\WINDOWS\system32\backgroundTaskHost.exe C:\Windows\System32\twinapi.appcore.dll 83dba75c-d113-4227-9bb5-5e25e3aeb400 Microsoft.People_10.0.3450.0_x64__8wekyb3d8bbwe x4c7a3b7dy2188y46d4ya362y19ac5a5805e5x The first, thing I did was to make sure that "File" permissions were not changed. All files were fine except for "Users" file. Which had All Application Packages missing. I have added All Application Packages with Full Control. The second, thing did was to check Registry. It didn't take me long time to find the problem was with HKEY_LOCAL_MACHINE subkeys BCD00000000, SAM, SECURITY, and SOFTWARE. Had to add All Application Packages with Read permission. I have not yet tested the computer to see if the fix has worked or not. I will update this article when I find out. I have tested Xbox App today. It's still crashing.