I've just received a "newsletter" from Firetrust, the makers of Mailwasher, the mail previewer I've been using for years. Keeps the obvious junk and viruses, etc. out of the inbox. The clip below is only a section of it.

For years I've denied read receipts in mail, since I feel it's intrusive asking for when I've seen a message, and I typically respond to non junk right away anyway. This program/script (MSGTAG) bypasses the "do you want to send the read receipt" and lets them know without warning or consent. Maybe it's just me, but I believe that this will only get thoroughly abused by spammers, looking to verify email addresses as valid more easily...allowing them to sell them for more money, and get us even more spam.
I find it incredible that a company whose products are intended to help against spam would then partner with another company that helps to increase it (even if only indirectly).

If it turns out that Mailwasher doesn't allow this to be blocked (I've opened a ticket there), does anyone know of a mail previewing program that downloads headers and some of the text for viewing without revealing that it's been seen? I'd liked MW because it wasn't susceptible to exploits and viruses, since it didn't 'understand' HTML or attachments. Pure plain text, thanks.
I'd just use Eudora (my email client), but it's a memory hog when you have several mailboxes open, and that's how I normally use it.

Hi, it's Nick Bolton from MailWasher.

I hope you got my recent newsletter about MSGTAG, a really useful bit of email software that tells you the exact moment when someone reads the email you sent them.

The response from our readers has been huge. I've had a lot of emails in the last few days from people saying how thrilled they are with MSGTAG and that they've been trying to find something like it for years.