Consuming "secure" web service

[Krokonoster]

I'm used to the "Normal" way of consuming a web service, where you "Add new service reference", etc.

Now I'm given a service url for a big client. When trying the normal way I got an error:
There was an error downloading 'https://aaaa.client.com/stuff/something/else/ListData.svc/$metadata'.

Not wanting to sound stupid, I asked the client's IT anyhow, and apparantly this web service wont send back the WSDL, so I cannot go that way.
He send me the wsdl file (and some xsd files) and I found a way to add service reference, specify that file instead and then modify your web.config.

Still no luck, getting an "Internal Server Error". Make me think the problem on their side, but since they so important and sounding confident that it's fine, I kept trying different things (for instance in my code create a binding, endpoint, etc which work for some other services, with still no luck.

They guy suggested using SoapUI for testing, which I downloaded (pro trial) but got no clue how the thing work.

Any idea what I'm talking about here and how to approach?

[abhijit]

yes. I am using soap UI all the time. If you're using a proxy server, you need to set the proxy server in the soap-UI preferences.

[jennysmith1]

You have to follow some instruction for security. Import the server certificate into the client and you should be able to use HTTPS URLs.

[Lightning]

You could user svcutil on the files hou received from the client