Call a webservice via ssl and use a client pass

I call a webservice via HttpWebRequest. Now the owner of the service send a key and said I would need to use it in the future to access the serv开发者_高级运维ice via ssl.

Is there any way to use this key? The key itself is similar to the key when you prepare your server for ssl.

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What sort of key have they provided? Assuming this key is an SSL client certificate, then the following link should explain everything you need to know about using it:

http://support.microsoft.com/kb/895971