I’m using EM Client to handle my uk2 emails. I upgraded to Windows 10 about a month ago and it has been working fine until yesterday when emails that I was sending wouldn’t leave my outbox. Apparently my uk2 settings are fine. I’ve tried an Outlook account and that sends and receives as it should do.
Any help would be appreciated.
Completely disable your anti-virus or firewall and try again.
I’ve just tried that and that has worked. Thanks. 
Obviously its going to be a bit of a pain to disable my anti-virus every time I want to send an email though! 
Is there anything I can do to work around this?
Yes, there should be settings in your anti-virus or firewall to allow eM Client to send while it is normally enabled.