So, I'm having an issue with the "Send Notification" workflow action. I want to specify a custom "From" email address for messages sent by this action. Specifically, I'm trying to use the "External email address" to specify the "from" email address. Nintex accepts the "External email address" I provide; however when I run the workflow in the message I receive the "from" is still the default email address. I've tried this in four different workflows, and I get the same result in all.
SharePoint 2013/Nintex Workflows/Nintex Forms Enterprise
What version are you running? Which external email address are you using?
I've tested on my server and managed to get it showed up on From in the email.