When I access Webmail remotely my changes, sent messages & deletions do not sync with my Shaw Mail that is on my desktop. And the same in reverse from Shaw Mail. What am I doing wrong?
Your desktop is using POP, which doesn't communicate with the webmail.
Your desktop might have the option to remove items from server when deleted from your computer, but the reverse wouldn't be true.
POP downloads the Inbox only, no other folders.
Retrieving data ...