I started to type this out then decided to find this link which explains it well. However..........

Note in that tutorial the different method when sending to everyone or just sending to selected people.

When you mention 'many senders' I assume you mean when a person has sent you an email they received from someone and failed to clear off all the names of those it was sent to originally? Just click 'Reply all'

I always remove all old addresses and all the added advertising on the bottom of emails, to me it is just common courtesy. Emails arrive to 'a special friend', how can one be special if the sender is too lazy to clean up the thing before sending on?

I agree it is one of my pet peevs that people treat our email addresses so carelessly, if I choose to share my personal info with someone I would hope they would treat it with some shred of respect and not spread it everywhere. Same as if I shared my phone number or other personal info, I do not expect to see it then plastered all over the place.
When we wonder where all that spam comes from well look no farther than all those emails that have your email address in a long list of forwarded ones those are a spammers dream.
Great link Owbist provided!

here are some good tips and great links to how to do many email tasks.
Remove All Email Addresses When You Forward a Message

I agree it is one of my pet peevs that people treat our email addresses so carelessly, if I choose to share my personal info with someone I would hope they would treat it with some shred of respect and not spread it everywhere.

Well said. More importantly I have never received one of those "you MUST forward this to EVERYONE you know..." kind messages that actually contained any useful information. Folks who feel the need to forward such vital information should, first check it's veracity (opening an email containing a picture of Sarah Palin isn't likely to cause your hard drive to melt even if you are a registered Democrat) and second, if you are hell bent on sending something to everyone you know, use the BCC field to address your message to protect the privacy of others.

If one needs to disseminate information on a regular basis to a large group of people, for example to provide updates on a medical condition, one is far better off using a mailing list where people can subscribe and unsubscribe as they wish.

Thank you's to the posters above. To say forwarded mail is a pet peeve for me is an understatement. Whether MS mail or any other available, if I am helping someone set up their pc, almost the first lesson I teach them is "this is the proper way to send email". BCC if you must and make sure the recipient wants to receive your junk mail.

I must take issue with any cavalier approach to an unsolicited e-mail with a picture. History shows viruses have been embedded in jpegs. Perhaps the poster was trying to be "light" in the topic, but with so many newbies and limited experience members here one must be specific in nature. Please don't open ANY unsolicited e-mail regardless of offering, subject or curiosity.

Also, as an added precaution a user may consider creating a message rule which will divert any forwards to automatic deletion. I've been doing it for years. My family and close friends know to not send anything forwarded as I will never see them.

DA

When I replied to the original poster I simply answered his/her question without regard to unwanted emails. As DA notes above, unwanted emails from unknown people should be instantly deleted without wondering who is sending what to you. If you do not know the sender then it can be fair to assume the content is not something you need and can be harmful.

I do not agree with DA on creating a rule to dump forwards if one enjoys receiving humourous emails. For him that is great of course and his circle of friends and family are aware of his actions. However for many people the 'funnies' are a large part of their computer enjoyment.

Of course it would be great if we could only teach those lazy people how to remove those dozens of addresses off the top and all the advertising off the bottom before sending things on to others.

sometimes even emails from people you know really are not from people you know! I just got an email from my nephew who often times sends me links to see his kids on little videos or picture albums. Yesterday when I got the email from him and noticed all the email addresses at the top that struck me as strange because he is like me and never leaves email addresses exposed, then on to the link, before I clicked it I hovered my mouse over it and looked down at the bottom of my browser to see if it would give the same address as the link well it did NOT, which let me know this was going to re-direct me somewhere else. That is how people end up on porn sites and infected sites with out knowing how they got there! Since I was on linux and was not afraid of infection I clicked the link and sure enough it took me to some viagra site. Which if I had gone there on my windows machines may well have tried to install some type of malware.
So I emailed my nephew immediately to let him know he had a problem. He thankfully was already aware of it and was scanning with malwarebytes to see what showed up.
Something had taken over his email and sent that out to everyone in his list which is why all those email addresses were showing, so it looked like it was from him but it was not really him that sent it.

So anytime you have a link in an email it is a very good idea to hover your mouse over it and see if it shows the same address down below as it does in the link. This is one reason I hate those short links since you have no idea what the link is going to.