If this is the desired effect you are looking for...you would do best to setup your accounts with IMAP instead of POP. google those two things to learn more about the differences between them.

It depends on what mail provider you use, not all email services allow IMAP.

POP is the most common configuration for mail clients, this will download a copies of your messages without changing the originals on the server (there is a setting somewhere in outlook on whether or not to delete the original message once downloaded, make sure this is disabled if you'll be using multiple computers)

IMAP is a 2-way connection, It will make any changes effected in outlook to the original copy. Using this standard any changes made in outlook will be seen on any device accessing the account as well as the web-based email interface.

Personally I like IMAP if you're going to access your account from multiple systems since your unread messages, deleted messages, spam, ect will always be right; but some people prefer pop since it gives you an extra layer of safety if you accidentally make a change you didn't want to.

-ps It doesn't if the two computers on connected to eachother on the network, they can be anywhere in the world and these differences will hold up, as long as their connected to the internet.

high this is franklin from ghana , yea am a young guy who is aspiring to be a computer guru please any information to help me achieve that ;franklinkrane@yahoo.com

you can set you client (outlook in this case) to

"leave a copy of the message on the server"

tools, email accounts, view or change, change, more settings, advanced tab.

do this on every machine that accesses that account.
then, every machine will see all the email.