I finally solved it. I had a mad tinkering half hour, and I finally, FINALLY worked it out. Here are those glorious settings for Apple's 'Mail' client for anyone who was as ...
Cheers, I hadn't thought of that. It's weird that it gives you the option of setting up a POP account - I assumed it supported both. I'll have a ganders.
My Orange.net email account was running fine in Mail until around Februaryish, and then randomly started refusing to send any emails. I rang customer services at the time, who told me to call tech sup ...