How to add Mailgun apikey or Office365 box In Heartsender V5?

How to add Mailgun apikey or Office365 box In Heartsender V5?

Dark and Light Theme
Multi Email List For every category
QR with multi size
Embedded Image
Html to image
Sending Speed improved with threads
zip Attachment
Improved and very easy to use GUI
Multiple proxies Allowed
Multi From Email with Letter
Multiple SMTP SUPPORT
Allowed SMTP and API
SPAM Words Detector
Allowed Multiple URL links Rotation
Multiple Threads Option
Reply Email Added
Multiple New inbox Letter Encryption added
SMTP TO SMS feature [ Monthly renewable ]
Customize Sender ID option

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