This may have been posted before, sorry if it was, probably even easier ways to do it. I needed to somehow sort out work emails (MS Exchange/Outlook)from Yahoo emails, a friend told me this hotkey way.
click on Messages icon
click on the Menu button
click on Search option
click on Service, click on Desktop
click on the Menu button
click Save
in Title area, give a name like MS Exchange Emails
go to Shortcut Key, click None
click any letter that, like Y, and that will become the shortcut key
click Menu
click Save
To see only the MS Exchange/Outlook emails
go to Messages icon, and click it (will see Yahoo emails and MS Exch there)
click Alt/Y (the hotkey you created)
you will now see only MS Exch/Outlook emails
to get back to see all emails, click back key near scroll ball, or go to Messages icon
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Also, when in your Yahoo icon email list, you can do same, Alt/Y, to sort that to work emails only
