[Outlook] Permanently changing email subject

I need to write a macro that will permanently change the subject of received mails in my account. At the moment, I'm using a simple code

Code:

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MyMail.Subject = MyMail.Subject & "READ"

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However, every time I restart the macro now, the subject lines are changed back to their original format.

How can I get the mail subjects to change permanently?

Try this:

Code:

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MyMail.Subject = MyMail.Subject & "READ"
myMail.Save

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