Error when creating App Packages

Does anybody understand what the following paragraph is trying to say?

What do I have to do to get rid of this error so that I can submit my app on Windows Store?

Any solution might help. Thanks!

'Libraries imported are as follows:
Imports Windows.Storage
Imports Windows.Web.Http
Imports Windows.UI.Popups
Imports Windows.Security.Cryptography
Imports System.Text
Imports System.Numerics
Imports WinRTXamlToolkit.Controls.DataVisualization.Charting

Error Found: The supported APIs test detected the following errors:

System.UnauthorizedAccessException: Access to the path 'C:\Program Files (x86)\Windows Kits\10\App Certification Kit\SupportedAPIs-x64.xml' is denied. at System.IO.__Error.WinIOError(Int32 errorCode, String maybeFullPath) at System.IO.FileStream.Init(String path, FileMode mode, FileAccess access, Int32 rights, Boolean useRights, FileShare share, Int32 bufferSize, FileOptions options, SECURITY_ATTRIBUTES secAttrs, String msgPath, Boolean bFromProxy, Boolean useLongPath, Boolean checkHost) at System.IO.FileStream..ctor(String path, FileMode mode, FileAccess access, FileShare share, Int32 bufferSize) at System.Xml.XmlDownloadManager.GetStream(Uri uri, ICredentials credentials, IWebProxy proxy, RequestCachePolicy cachePolicy) at System.Xml.XmlUrlResolver.GetEntity(Uri absoluteUri, String role, Type ofObjectToReturn) at System.Xml.XmlTextReaderImpl.OpenUrlDelegate(Object xmlResolver) at System.Runtime.CompilerServices.RuntimeHelpers.ExecuteCodeWithGuaranteedCleanup(TryCode code, CleanupCode backoutCode, Object userData) at System.Threading.CompressedStack.Run(CompressedStack compressedStack, ContextCallback callback, Object state) at System.Xml.XmlTextReaderImpl.OpenUrl() at System.Xml.XmlTextReaderImpl.Read() at System.Xml.XmlLoader.Load(XmlDocument doc, XmlReader reader, Boolean preserveWhitespace) at System.Xml.XmlDocument.Load(XmlReader reader) at System.Xml.XmlDocument.Load(String filename) at Microsoft.Windows.SoftwareLogo.Tests.SupportedApis.SupportedApis.GetNativeAllowList() at Microsoft.Windows.SoftwareLogo.Tests.SupportedApis.SupportedApis.ExecuteSharedTests(EnumApplicationType appType, String packageFullName) at Microsoft.Windows.SoftwareLogo.Tests.SupportedApis.SupportedApis.Test(UapApp uapApp) at Microsoft.Windows.SoftwareLogo.TestBase.TestBase.ExecuteTest() [HRESULT 0x80131604] Test operation failed: 'ExecuteTest'.

Impact if not fixed: Using an API that is not part of the Windows SDK for Windows Store apps violates the Windows Store certification requirements.

How to fix: Review the error messages to identify the API that is not part of the Windows SDK for Windows Store apps. Please note, apps that are built in a debug configuration or without .NET Native enabled (where applicable) can fail this test as these environments may pull in unsupported APIs. Retest your app in a release configuration, and with .NET Native enabled if applicable. See the link below for more information: Alternatives to Windows APIs in Windows Store apps.

had had the same problem. The owner of the file SupportedAPIs-x64.xml had been set to none, so I changed it to the SYSTEM. Also under Permissions there had been a line SYSTEM and other columns for this principal had been empty. There were another principal SYSTEM and its other columns were ok. So I deleted the first SYSTEM principal and everything was OK. Just open properties of that file and under Security click on Advanced button. Basically I compared permissions of the file with permissions of the SupportedAPIs-x86.xml. Try to open the file in notepad, if it works.