Visual Studio 2010: What is a .pfk file?

Question

I recently found out about Visual Studio's ability to create a Setup.exe file for your project when you publish the project (Build -> Publish [Project Name]). When I've done this I noticed a new file being added to my project with the name "[Project Name]_TemporaryKey.pfk" (so if the project was HelloWorld the .pfk would be "HelloWorld_TemporaryKey.pfk").

What is this file and why do I need it?

Do I need a "PermanentKey" at some point?

Thanks for your help.

Answer 1

A .pfk file is Personal Information Exchange file that is used to "sign" your Visual Studio assemblies.

Assembly signing (also called strong-name signing) gives an application or component a unique identity that other software can use to identify and refer explicitly to it. A strong name consists of its simple text name, version number, culture information (if provided), plus a public/private key pair. This information is stored in a key file; this can be a Personal Information Exchange (PFX) file or a certificate from the current user's Windows certificate store. More information can be obtained here.

I haven't worked with them much but I believe the link(s) below may shed some light on their use:

The Use of .PFK and .SNK files

Signing an Assembly - MSDN Documentation

Hope these helped.