If you have an email locked and need to lock others to close them out since you are resolving the concern via phone or in another email... 

  1. Click the search icon at the top near the word email

 

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2. A text box will open, enter the email address you want to search. If you need to do a more complex search, click the little box that looks like a spreadsheet next to the text field.

 

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Once the results display, you can lock the other emails to assign them to you. 

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