You can enable the inline comment feature in Outlook, and add your username or other custom strings into replying message within brackets. Please do as follows:

1. Click File > Options to open the Outlook Options dialog box.

2. In the Outlook Options dialog box, click Mail in the left bar, check the preface comments with options in the Replies and forwards section, and type your username or custom strings into the following box. See screenshot:

3. Click the OK button to close the Outlook Options dialog box.

From now on, when replying an email in Outlook, the specified username or custom strings embraced with brackets will be inserted automatically only if you type inline comments amount original message. See screenshot:

Easily reply with sender name as auto personal greeting in Outlook

Most of time, you manually type Hi/Hello sender name as greeting in replying messages in Outlook. But, with fantastic Auto Greeting feature of Kutools for Outlook, greeting word and selected email's sender name will be added in replying message automatically as personal greeting as below screenshot. Save time!

If you are working in Outlook 2010 with Kutools for Outlook installed, you can reply with comment which contains your username.

1. In the Mail view, select the email you will reply, and click Home > Reply.

2. In the replying message window, select the content as you need, and click Kutools > New Comment.

And now a comment is added besides message body, and your username is added at the beginning of comment. See screenshot:

3. Compose the replying message and send it.

If you have Kutools for Outlook installed, you can also reply with sender name as auto greeting in replying messages. Please do as follows:

1. Click Kutools > Options.

2. In the opening Options dialog box, go to the Reply tab, check the Add greeting when reply option in the Greeting section, type Hi <<SenderName>>, into below box, and click the OK button. See screenshot above.

3. In the Mail view, select the email you will reply, and click Home > Reply.

And now Hello SenderName (SenderName will be replaced with you selected email’s sender name) is added at the top of message body. See screenshot.

4. Please compose the replying message and send it.

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