Comments below.

Signature
Sue Mosher, Outlook MVP
Author of
Microsoft Outlook Programming - Jumpstart for
Administrators, Power Users, and Developers
http://www.outlookcode.com/jumpstart.aspx
> I have designed a custom form based on Message template. I create a
> message in it and then Save it, by pressing a button on the form, to a
[quoted text clipped - 3 lines]
> separate copy of the message. How can i identify that current item is
> infact opened from the folder, not the New form.
When the first save operation occurs, set a flag property on the item to
indicate that the item has already gone through the process. Check the value
of that property on subsequent saves and have your code proceed accordingly.
> I have another question. If i have saved a custom form based item to
> some folder. Now in Addin Code, i get All Items in that folder. Can i
> get contents of the custom controls i inserted on the form in addition
> to standard controls like Subject, Body etc. My custom controls include
> Text Boxes and Combo Boxes.
Yes, you can do this, using the same code as behind a form, but why? The
"contents" of the controls are the property values stored in the item, which
you can access directly. See http://www.outlookcode.com/d/propsyntax.htm