From: Leigh on
Greetings,

I know that lots of viruses can come with email attachments and in the email
itself.

Here is my question.

When I read my email that comes from my ISP email account I believe the
email is downloaded onto my Dell computer and is taken off of the ISP's
servers.

Now I am not sure about Web based email accounts like Yahoo! G mail, etc.

When I read an email from my Web based account am I reading the email from
the Web based server? I know that if I download and attachment from a Web
based email the attachment will come onto my hard drive, but what about just
a letter. Will that be downloaded onto my computer or am I reading letter
from their Web based servers and the letter is not downloaded to my
computer?

I hope you understand my question.

Thanks in advance for your help and support.

Leigh


From: William R. Walsh on
Hi!

> I know that lots of viruses can come with email attachments and in
> the email itself.

> When I read my email that comes from my ISP email account I
> believe the email is downloaded onto my Dell computer and is taken
> off of the ISP's servers.

Generally speaking, that is 100% correct. Most people retrieve their e-
mail over a POP (post office protocol) connection to their ISP's e-
mail server. And when you download those messages, everything attached
to them usually comes along for the ride.

There are some mail programs that can be set to download only message
bodies without attachments, or with attachments that fall under a
certain size. Some mail programs may also be set to leave messages on
the server (in case you plan to retrieve them later from another
computer).

> When I read an email from my Web based account am I reading the
> email from the Web based server?

Yes, that is correct. The web mail service will only serve what you
requested to see--so if all you ask to see is the message, there's no
point in delivering the attachment. Everything there is delivered upon
demand.

This can mean that there is an increased measure of safety in using
web mail services to read your mail. On a conventional POP mail setup
(as described above), you download everything by default. It can then
be assumed (by the writer of a virus) that since both pieces of the
message are together, an attack could be attempted. It would only be
successful if they knew what mail program you were using, knew of a
security vulnerability within that program or if they took a guess on
the two previous points and got lucky. Mail clients (especially
Microsoft's Outlook product) have become a lot more hardened since
such exploits were demonstrated many years ago.

It would be at least theoretically possible to do the same from a web
mail account. But I'd expect it to be much harder, as the attacker
would likely have to know the URL that should be sent back to the web
mail provider to retrieve the attachment. They'd also have to do a lot
of fancy trickery with scripting and exploiting security holes in your
browser to force an action to be taken with the malicious attachment.

> Will that be downloaded onto my computer or am I reading letter
> from their Web based servers and the letter is not downloaded to my
> computer?

You are reading the letter from their servers...but...unless
specifically instructed not to, your web browser will cache a copy of
whatever web page you are presently viewing. That includes the pages
served by your web mail service. The cache is stored on your computer,
but it probably won't stay for very long as the space occupied is
small and gets used over and over again.

It will only contain web pages that you have chosen to view.

William
From: Leigh on

"Leigh" <lgh(a)cts.com> wrote in message
news:4b508516$0$5346$bbae4d71(a)news.suddenlink.net...
> Greetings,
>
> I know that lots of viruses can come with email attachments and in the
> email itself.
>
> Here is my question.
>
> When I read my email that comes from my ISP email account I believe the
> email is downloaded onto my Dell computer and is taken off of the ISP's
> servers.
>
> Now I am not sure about Web based email accounts like Yahoo! G mail, etc.
>
> When I read an email from my Web based account am I reading the email from
> the Web based server? I know that if I download and attachment from a Web
> based email the attachment will come onto my hard drive, but what about
> just a letter. Will that be downloaded onto my computer or am I reading
> letter from their Web based servers and the letter is not downloaded to my
> computer?
>
> I hope you understand my question.
>
> Thanks in advance for your help and support.
>
> Leigh
>

Thanks for your responses