In order to set up forwarding of all emails except for junk, a rule must be created in a mail client or OWA. This article describes creation of such a rule in

To create such a rule, log in to Webmail for the user whose emails are to be forwarded to someone else. The other user to whom emails will be forwarded should be either another user on the account or a Company Contact for your account.

Navigate to Options > See All Options.
Navigate to Organize E-mail > Inbox Rules > New.
Under Apply this rule, click Select one and select [Apply to all messages].
Under Do the following, click Select one and select Redirect the message to....
Select the user from the Address Book.
Click More Options.
Click Add Exception.
Under Except if, click Select one and select It includes these words > in the message header....
Type X-Spam-Flag: YES > click plus sign (+) > click OK.
Click Save.

Now Junk email messages will not be forwarded to the other user.