Day one problems!

I signed up with zoho today, after my yahoo account was hacked. I then tried to use my lovely new zoho account to inform all my contacts - over 300, I now realise - of my new address, as well as to apologise for the spam they received from my yahoo account hijacker.

I now can't send email.

Additionally, I can't open the emails already downloaded to outlook - I get this dialogue box: 'This message has not been fully downloaded. Would you like to unmark it for download?'

I'd be incredibly grateful for any help on this!