Nowadays when I want technical support I will email my web host and give them all the necessary information, i.e. what I have tried to do to resolve, what I think the problem is etc and usually it is fixed first time within a few hours. If I need urgent assistance I will ring them but 99% of the time email is sufficient and less stressful, rarely do I need to send a second email.

If you email helpdesk (us specifically), if you use appropriate technical detail you will probably get someone who knows what they're doing, and will greatly appreciate it. If you call, you will get me only. I will ask you lots of questions, with awkward pauses in between while I write my notes, and at the end of it I probably won't be able to help you. Technical detail is still welcome, but there are some questions I will ask you anyway even if they sound useless to you

Calling over e-mailing has a number of advantages, you're able to empathize with the person and they're able to hear how comfortable you are with the topic over the phone.