Edited Issue: "The parameter is incorrect" when loading a Certificat [53]

I have receive a "debug info" file from an anonymous user which try to load a file as a new certificat. When loading this certificat, Wsus throw an Exception "The parameter is incorrect'.
The only way to reproduce this error was to rename a non pfx file as *.pfx.

Wsus can only accept pfx file as certificat.
Add security in the code to avoid a user to try importing a certificat from a remote computer without SSL connection. Add a check to verify the imported file.