Part 1: Add the Location field has been added to the Project Template(s) you’re using
Part 2: Update a project to include its Location

Part One: Add the Location field

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to the Project Template(s) you’re using

Select My Apps in the top menu
Select Project Templates
You arrive on the Project Templates page
The table shows you which projects are associated with each Template
Press the cog button next to the Project Template you want to edit in the Tools column
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Select Edit
You arrive on the Edit Project Template page
If Location is not listed in the Current Fields column on the right, select it from the Available Fields section on the left
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Scroll to the bottom and press Save

Select My Apps in the top menu
Select Projects
Switch to Table view
Press the More Options (cog) button next to the project you want to add a location to
A dropdown list appears
Select Edit & Rename
You arrive on the Edit Project page
The Location field will be visible
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Start typing in the location of the project. A Google Maps lookup will help you select the specific address
Press Save