Self signed certificate IIS7 - The remote certificate is invalid according to the validation procedure

I have a website hosted on my web server contacting a secure web service on another server. I have created a self signed certificate and attached it to the https:// binding. I have done 2 things to try and accept the certificate on my web server:

1. Open IE and browse to my wsdl file in the web service - Installed the certificate to the Trusted Root Cert Authority.
2. Exported the certificate from the other server, gone into M开发者_StackOverflow社区MC and installed imported it manually into the Local Computer Trusted Root Cert Auth.

Neither of these have worked and I am not sure which route to try next.

System: Windows Server 2008 running IIS7.

Many thanks for your time.

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I had to do this the way everyone else seems to do it by overriding the certificate check. Not what I wanted but has sorted it for now.