Make column look at Active Directory and auto populate - SharePoint Designer 2013

Question

I'm using SharePoint Designer 2013 and I have a list that I created from an excel spreadsheet that have several columns and rows. One Column is labeled as "Assigned To", it may have some data populated in a couple of rows but a majority are just left blank currently.

My problem is I cannot figure out how to force that column to search Active Directory for results. I would like to either make it so the user clicks a button and they can search active directory or as they type names a persons name will show up as auto populated data. Then once they save that item that user that was just assigned the item will get an email saying it was assigned to them.

I have tried looking at a couple solutions like: solution1, and solution2. However I could not get mine to work, perhaps I was doing it incorrectly.

Answer 1

Go in List Settings>select your Assigned To column - is it a Person or Group field or something different? A Person or Group field uses the names you find in Active Directory as it's data source.

Importing an Excel file and converting it to a list can be a useful time saver, but it's possible Sharepoint created the wrong field type.

Regarding sending an email out - please see this link with a step-by-step guide on configuring a simple workflow and making an email notification be triggered. Please pay special attention to the Start Options (see section 15), as this confused me for a while. Just test it by making the emails be sent to you initially until you're happy it's working correctly.