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Does a sender know when I open an email?

  • 4 replies
  • 1 has this problem
  • 28 views
  • Last reply by Zenos

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I already have Thunderbird set up to put spam in the spam folder, but occasionally it puts a wanted email into spam, so I always have to check through the spam folder. Recently I have started getting an absolute avalanche (at least a dozen a day) of particularly obscene spam advertising how I can get any young girl laid whether she likes it or not. I am 80, and rather past this kind of high jinks! They come from a wide variety of senders (or I suspect one sender but a wide variety of addresses) so it's difficult to block the senders. My first question is: If I open them to delete them, does the sender know I've opened them, and uses that information to send more, or is there no such feedback? I know I can delete them one by one without opening by right clicking and selecting delete, or I can select them all and press delete, but then I've opened them all. I can't disable the message pane because in version 31.2.0 under "view" there is no "layout>message pane". So if the answer to my first question is "yes" how can I delete a block of messages without opening them?

I already have Thunderbird set up to put spam in the spam folder, but occasionally it puts a wanted email into spam, so I always have to check through the spam folder. Recently I have started getting an absolute avalanche (at least a dozen a day) of particularly obscene spam advertising how I can get any young girl laid whether she likes it or not. I am 80, and rather past this kind of high jinks! They come from a wide variety of senders (or I suspect one sender but a wide variety of addresses) so it's difficult to block the senders. My first question is: If I open them to delete them, does the sender know I've opened them, and uses that information to send more, or is there no such feedback? I know I can delete them one by one without opening by right clicking and selecting delete, or I can select them all and press delete, but then I've opened them all. I can't disable the message pane because in version 31.2.0 under "view" there is no "layout>message pane". So if the answer to my first question is "yes" how can I delete a block of messages without opening them?

Chosen solution

If they are sufficiently cunning, they may use something called a web bug; usually an invisible 1-pixel picture. The act of you viewing the message requests the image to be downloaded from a server, and they can track this download happening.

There are two simple ways to thwart it.

  1. View your messages in plain text. This means that thunderbird looks only at the plain text part of the message, ignores the graphic content, and so avoids the download request.
  2. Read your email when offline. Thunderbird will attempt to fetch graphic content, but the lack of a connection will cause it to fail.

In both cases you need to take care to neutralize the message so it doesn't get a chance to do its phone home thing. So delete it, or sanitize it if you really want or need to keep it.

There are mail providers who claim to be able to track delivery and reading, but they generally use tricks like these, or scripts that run when the message is viewed (but Thunderbird doesn't run scripts). Again, reading such messages offline is generally effective in defeating the tracking.

In short, a normal email user can't track your reading. He needs to be running a webserver to use a web bug, or he needs to have engaged a mailing delivery and tracking service.

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All Replies (4)

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Thunderbird does not run code in their message viewing so unless you click a link it is high improbable that you are going to send any kind of message acknowledgement back to the spammer.

FYI: The Message Pane choice is hidden under Options-Layout in the new and not improved menu system. The shortcut of F8 still works just fine to toggle the message pane on and off.

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There seem to be two issues here: deleting without opening; and getting rid of the message pane. You can close the message pane by clicking on the line that separates it from the message list and dragging it down until it disappears. Then when you *single* click on a message, it will not open and the sender will not get any feedback that you received it. As far as deleting messages, there are several ways: when one is highlighted, you can press the Delete key; as you mentioned you can right click and select delete (a slow process); or you can *single* left click on one message and then holding down the Control key *single* left click on additional messages (each gets highlighted). Then let go of Control and press Delete. If you want to get rid of all of them at once, *single* left click on one, then hold down Control and press A. All should be highlighted. Then press Delete.

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Many thanks to both of you for your helpful replies, particularly the f8 trick to close or open the message pane. Just to confirm - if I DO open a message, can the sender find out I have opened it without my knowledge or choice?

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Chosen Solution

If they are sufficiently cunning, they may use something called a web bug; usually an invisible 1-pixel picture. The act of you viewing the message requests the image to be downloaded from a server, and they can track this download happening.

There are two simple ways to thwart it.

  1. View your messages in plain text. This means that thunderbird looks only at the plain text part of the message, ignores the graphic content, and so avoids the download request.
  2. Read your email when offline. Thunderbird will attempt to fetch graphic content, but the lack of a connection will cause it to fail.

In both cases you need to take care to neutralize the message so it doesn't get a chance to do its phone home thing. So delete it, or sanitize it if you really want or need to keep it.

There are mail providers who claim to be able to track delivery and reading, but they generally use tricks like these, or scripts that run when the message is viewed (but Thunderbird doesn't run scripts). Again, reading such messages offline is generally effective in defeating the tracking.

In short, a normal email user can't track your reading. He needs to be running a webserver to use a web bug, or he needs to have engaged a mailing delivery and tracking service.

Modified by Zenos