When using a WebRole, you automatically get IIS and a HTTP InputEndpoint listening on port 80. If you have multiple WebRoles an arbitrary portnumber is assigned to the latter WebRole.
So, long story short,.... In the management portal you can see what ports are used. I can imagine that your WebRole is not listening on port 80 and you could experience that as not being able to connect, since you'd have to append the portnumber to the host
Can you give us a bit more detail or describe what's mentioned in the management portal?
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