How can you confirm that you have responded to a client's email using VBA?

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One way to confirm that you have responded to a client's email using VBA is to create a code that would mark the email as responded in Outlook. This can be done by setting the "FlagStatus" property of the email item to "olFlagComplete" or "olFlagMarked". You can also create a new folder and move the original email and the response email into that folder to keep track of your communication with the client. Additionally, you can create a custom log or report that would list all the emails that you have responded to, along with their corresponding dates and times.