First, connect to office.com and log in. Then select the Outlook icon circled below.

Once you've logged in and have Outlook open in a tab, click on your icon in the upper right.

Select Open another mailbox and start typing the box you need access to.  Remember, all NYSERDA shared mailboxes start with "erda.sm".

It may autocomplete. If it does, just select it and click open.

The shared mailbox will open as a new tab in your browser.

You can then work inside that box just like your regular Outlook account!