SignTool error when signing AppX file: "Error: SignerSign() failed." (-2147024693/0x800700cb)

I am creating an Appx package using makeappx.exe and then try to sign it using SignTool.exe.

The error I get from SignTool is:

"Error: SignerSign() failed." (-2147024693/0x800700cb)

The certificate I am using is created by me following instructions from here.

In EventViewer there is no record about this failed operation!

I do not understand what this error means and how to fix it!! Has anyone encountered this before, and found a solution?

I can't use Visual Studio so I need to stick with makeappx.exe.

The appxmanifest xml file needs to have a publisher that corresponds to the certificate that is signing the appx package. The publisher is specified in an attribute for the "<Identity />" tag.

From MSDN:

The app manifest publisher name must exactly match the subject name of the signing. Note These names are specified in quotes and are both case and whitespace sensitive. You can update the Publisher attribute string that is defined for the Identity element in the AppxManifest.xml file to match the subject name of the intended signing certificate. Or, select a different signing certificate with a subject name that matches the app manifest publisher name. The manifest publisher name and the certificate subject name are both listed in the event message.

Example error:

error 0x8007000B: The app manifest publisher name (CN=Contoso) must match the subject name of the signing certificate (CN=Contoso, C=US).