We recently had anew consultant join us at ISC Software which meant building a new laptop. As she lives fairly near me the laptop and other kit was delivered to me and I did some setup. Once she was logged on there was one unexpected issue with emails not sending in Outlook.
I did some checking of settings and found that there is a setting which needed to be enabled for sending of emails; I'm not sure why it was not set as I don't recall having set it previously.
The setting is in (); select the Advanced tab and, under Send and receive, mark the Send immediately when connected checkbox:
Once the options were saved, emails were correctly sending.