There is only one file type that uses the .P7X extension:
Packed Digital Signature File
File created by Microsoft Visual Studio, A Windows SDK; contains data, including a digital signature, to verify that the contents of the Windows Store application haven't been modified after they were digitally signed; held within an .APPX package file.
The P7X file is one of four main parts of an APPX package file:
- App payload - App code files.
- App manifest - App manifest .XML file.
- App block map - App package XML block map file.
- App signature - P7X file.
The P7X file will appear as AppxSignature.p7x in the subdirectory of the Windows Store application.
AppxSignature.p7x - Default name of the digitally signed file for each Windows Store application.
Updated: March 20, 2017