Digital signature on e-mails?

Why the big software companies don't push to make digital signatures a must on e-mails?

I know it will take time, but shouldn't they start working on it to eventually have it in the future?

Today nobody uses digital signatures, so the antispam rules on my email have to trust on the sender address which is very easy to manipulate, or even a virus can send an email from a friend's computer.

With some effort the email software should be able not only to filter non-signed e-mails from senders that are supposed to send a signature, but the digital signature should also be unaccessible for automatic processes like virus to be sent without the user intervention.

Digital signatures could be acquired for free when you open an email account.

For a world clean of spam...

Digital signature on e-mails?antispam

it has to do with too much power in the hands of people.how do you know that some guy cannot make the same signature as they can? it is more about not taking any chances and not being pushed because technology is always changing so no matter what they do they would have to be at least a couple of steps in front of everyone else and to spend extra money on updates every so often.a co. would rather be safe than sorry in case the info gets in the wrong hands..maybe later on signatures would be used but as of right know we have people who are expects in computers and can hack into computers and do what they need to which makes companies more vulnerable ..maybe companies and the emails will take their time yet they would have to be super effiecient against today's advances in technology which occur very often.

Digital signature on e-mails?avast

have you ever seen how many companys can create digital signatures? it gets to be too many then I wouldnt even trust them, dont know your answer but thats all I can say about it.