If you are unable to send emails through Microsoft Outlook it is most likely because there is a space in your Windows user name. This issue was identified in the Sage 50 Accounting 2016.3 release and we have addressed this issue by releasing a patch for Sage 50 Accounting 2016.3.
The hot fix is available through the Sage 50 customer support team and is posted in the Sage 50 knowledgebase. We are not distributing this service pack to all our customers and Sage Accountant Network members as an automatic update since this only impacts a small number of businesses.
In addition, we would like to make you aware that if a recipient’s email address has a dash, space or underscore prior to the “@” sign in their email address, you will get a message about an invalid email address. This fix is not included in the hot fix and therefore a different email address will need to be used.
The above issues will be fixed in the Sage 50 Accounting 2017.0 release.
We apologize for any inconvenience this issue has caused.
Sage 50 Accounting Team