1. Click “Tools,” then choose “Options.”
2. Select “Security.” Click the “Passwords” tab and then the “Saved Passwords” button to open the Saved Passwords window.
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4. Select the account whose password you wish to change. Then click the ‘Show Password’ to display the password and enable sa Edit Mode.
Note : Since we want to change the SMTP password, make sure you choose the one with the prefix of SMTP.
5. Right Click on the selected account then choose ‘Edit Password’
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6. Type-in the new password.
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7. Then hit ‘Enter’ key to save the changes