[RESOLVED] Cannot send a CDO message

Hi everyone,
I'm trying to send a simple CDO message from a classic ASP page (using VBScript), but keep getting this
error:
The server rejected one or more recipient addresses. The server response was: 550 5.7.606 Access denied, banned sending IP [217.69.37.136].

The host name that I have been provided with has the format: ''(servername).mail.protection.outlook.com', and all the server settings (i.e. port, UN/PW etc.) are correct.

I'm using my own address as both the mailObj.From field and the mailObj.To field.

I'm testing the site from my own web server before loading it onto the client's server, but surely this shouldn't affect the mail process.

I've tried looking at http://go.microsoft.com/fwlink/?LinkID=526655 but I don't like messing around with Blocked Senders Lists on someone else's server.

Can anyone help lease?

Thanks