Please explain more on what you’re trying to do.
I have a home desktop and my wife & I each have a laptop. I would like all three to be synced.
All three sharing the same e-mail address?
Okay, end-user purpose mail program usually don’t have built-in database sync feature. This can be achieved by 3rd party software, but it a bit complex to set it up. The easiest way to receive e-mail from the same address is to use IMAP server if your mail provider support it. If not, you can achieve this in POP3 by changer the server setting as follows.
On you menu -> Tools -> Accounts -> (your mail account) -> POP3 -> Server Settings. Enable “Leave a copy of message on the server” and “Remove from server after x days”. You can set the duration, something like 10 days should be enough time to retrieve on all 3 PCs.