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Outlook Auto-Complete / Auto-Fill Email Address Not Working Problem Solution
One of the great things about online email services like Gmail is that you never have to worry about things like autocomplete because all of your contacts are stored in the cloud and Gmail automatically creates a giant index of everyone who has emailed you or everyone you have emailed. When you start typing a name or email address, all of the matching contacts magically appear!
That’s not the case with Outlook 2016 or earlier versions of Outlook. Nothing is stored in the cloud, so everything is based on local files. That includes the autocomplete suggestion feature. Basically, every time you type a name or email address in Outlook, it’s saved to a file, and the next time you type that name or email, it’s autocompleted for you.
Please note: If you are working in a corporate environment, your contacts are technically stored in the cloud (Exchange server).
