vb.net - Properties - SIGNING - Sign the click once manifest

I see this in the properties area..how can I learn more about what this is doing in my vb.net app..im using visual web dev 2008 express

I know that click once is for deploying updates from to the clinet apps from the server....but i didnt think that this shipped with with viz web dev express ..only viz studio proper...

also what does the "Select from Store" do?

I click this and it brings up a pop up...select a certificate to sign your click once...

When I click on the Create Test Certificate....the popup comes up and says "Enter password for xxx_temporaryKey.pfx"

What is this??? What is a .pfx file??


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then under the Security tab...it says "Enable ClickOnce security Settings"

Is this so I can can stipulate waht parts of the app will have certain access??thanks for help

I have one one in there from a developer and I want to delete..I have no idea how it got there

it says valid from 6/3/2010 to 6/6/2011...does he have unauthorized access???  to my app?