In digging further into the subject of receiving a notification that my mail has been opened, I was sidetracked by the security issue of IP being included in the Email providers Header information. This inclusion can immediately reveal a lot of personal details about the sender - geographic location and map, details of the OS system, the server, sender details and much more. Some IP finders give an astonishing amount of location and system information.
A few of the more comprehensive Email trackers use this Header information to give the sender and recipient all of this data. Occasionally the location is inaccurate, but often it is fairly good and it can be almost exact.
With any received Email, open it and click on the item marked " Full Header" or "Show original" as in my case using Gmail. The senders IP is under "X-originating IP" in the latter part of the text. Once you have that, you can manually check it out using one of the many free IP finders - http://www.ip-tracker.org/ is just one. Then you have a very detailed account of who sent the mail and from where.
Gmail does NOT include the senders or recipients IP in their Header data. The IP`s given in the Gmail Header are for Google`s servers. So Gmail must be ranked as an extremely secure Email facility, indeed one of the best. I do know that Yahoo DOES include the senders IP in their Header data and probably most other Email providers do the same. My OE6 includes the senders IP in the Header data, but Hotmail does not include the senders IP in their Header and as Outlook.com is the same MS equivalen updated, then neither will they.
The bottom line is that Gmail cannot reveal the senders profile since the IP data used are server proxies. Gmail is still committed to sending a simple "Your Email has been read" message when a tracking system is used. Rather like MSGTAG does. But that is not generated by any IP, but by inserted hidden images, pixels or sensitive text in the received mail. A PC using an image blocking selection, is not HTML and is using plain text will not activate a tracking response.
All Email trackers usually employ invisible implanted images, a tiny unseen 1 pixel image or an added electro-sensitive text suffix to the recipients address, this text being invisible to the recipient. Some trackers offer the option of a visible image, but it is general practice not to let the recipient know they have been tracked. MSGTAG do let the recipient know that they have been tracked with a box at the bottom of the message saying :-
"MSGTAG has notified the sender that this message has been received."
I am no expert on IP or Email tracking. What I have found out is good enough for my information purposes, but surfing the subject on the web will result in a detailed, somewhat complex and extensive coverage of the issue.