title: Signing a Windows Store application with a corporate certificate
body: <p>We are trying to sign a Windows 8.1 Store application with a corporate certificate obtained from Symantec. The certificate was originally ordered for Windows Phone 8 application signing, but the same certificate should work for Windows 8.1 apps also.</p>
  
  <p>On a fresh Hello World -project, when we try to choose the certificate from the manifest designer in Visual Studio 2013, an error message is given: "The Manifest Designer could not import the certificate. The certificate you selected is not valid for signing because it is either expired or has another issue. For more information, see <a href="http://go.microsoft.com/fwlink/?LinkId=241478" rel="nofollow noreferrer">http://go.microsoft.com/fwlink/?LinkId=241478</a>." </p>
  
  <p>The certificate is most certainly not expired. On the "another issue" angle, a common suggestion for a possible cause for this issue was a publisher name mismatch between the certificate and the application, but that has been ruled out. If we skip some signing checks by adding a EnableSigningChecks=false to the .csproj file, we can sign the app, but then another error is given by PowerShell when trying to install the application: "Error: The certificate can't have the following extended key usage: 2.16.840.1.113733.1.8.52.1." Only the Code Signing and Lifetime Signing EKUs are allowed." </p>
  
  <p>We asked for help on this issue from Symantec and Microsoft, but they didn't know how to help with this issue.</p>
  
  <p>Has anybody encountered a similar issue with signing their apps? Is there a solution to this problem? </p>
  
  <p>This issue looks to be the same as in <a href="https://stackoverflow.com/questions/22288410/choosing-a-certificate-for-a-windows-store-application-via-the-package-appxmanif">Choosing a certificate for a Windows Store application via the package.appxmanifest</a>, where the solution was to get a new certificate. Is the only thing we can do to just buy a new certificate?</p>