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Clear address cache in Entourage

How to stop auto complete address suggestion in Entourage?

Entourage If you want you Entourage to stop giving you suggestions of old Email addresses while typing the name, then you can follow the steps mentioned below. This is really useful when someone who is in your address list and you have sent him/her mail earlier but now their Email address is changed. In this case Entourage will keep suggesting you the old address which is cached in the memory. You can clear the address cache by following this small step:
Go to Preferences under Entourage menu.
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Select Compose and under Recent Addresses, click on the button “Clear List”.
Picture 3 Doing this will make Entourage forget all the addresses saved in cache. 
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If you want to disable this feature entirely and have Entourage only offer auto-complete for addresses in your address book, simply uncheck the option "Display a list of recently used addresses when address messages".