tell eM client to keep messages on server for a period of time?

I have one email account that goes into two different computers. How do I tell eM Client to keep messages on my server for 7 days so I know each computer will get all the messages downloaded?

Hi,
what email protocol do you use (IMAP or POP) ? And what mechanism is in control of deleting or not keeping messages at server, can you describe?

Hi Gabriel,
I figured this part out.

I am using POP and in my eM client I went to Tools, Accounts, POP and clicked on save messages on server and put in 7 days. So I THOUGHT that would solve my real problem. But it didn’t.

Here’s the deal. I have an email address that comes in on more than one computer. My desktop seems to get all the messages from the server. But my laptop only gets some of them. I thought it was maybe because if my email program was open on the desktop and the messages came in but then were deleted from the server it might be why the laptop wasn’t getting them. But that’s obviously not the case. Today I had about 20 messages come into my desktop but only about half of them showed up on my laptop.

Is there something I’m missing?? This only seems to have become a problem since I started using eM client on my desktop. If you have any suggestions, PLEASE let me know.