HTC Desire HD User Manual page 101

101 Email
3. Enter the Exchange ActiveSync account details, and then tap Next. Your
corporate Exchange Server must support auto-detect for the phone to
automatically set up the Exchange ActiveSync account. If your corporate
Exchange Server does not support auto-detect, you'll need to enter your
Exchange Server settings after you tap Next. Ask your Exchange Server
administrator for details.
4. Choose the types of information you want to sync. Also choose how often you
want to update and sync email to your phone.
5. Tap Finish setup.
Checking your Mail inbox
When you open the Mail app, it displays the inbox of one of your email accounts that
you've set up on your phone. To switch between email accounts, tap the bar that
shows the current email account, and then tap another account.
Viewing the unified inbox of all your email accounts
You can view email from all your accounts just in one place without having to switch to
different accounts.
Just tap the bar that shows the current email account, and then tap All accounts.
Email messages are color coded so you can easily distinguish which email accounts
they belong to.
Up to 15 email accounts can be shown in the unified inbox.