By
default, Windows Phone checks for new mail automatically. How often it
checks depends on the account. The default for web accounts is every 30
minutes. Exchange accounts, on the other hand, are usually configured to
deliver—or “push”—a message to your phone the instant someone sends it.
But there’s a tradeoff to timeliness: The more frequently your phone
checks for new messages, the more battery power it uses up. If you don’t
like the default automated schedule, you can easily change it—or
manually sync your mail any time you like.
1. Check Manually
On the Start screen, tap an e-mail account.

Tap Sync to check for new messages.

Tip:
Tap Settings > Ringtones
& Sounds > New Email to change the alert sound your phone plays
when an e-mail arrives—or to switch to blissful silence.
2. Change Sync Settings
On the Start screen, flick left to the Apps list or tap the arrow.

Tap Settings.

Tap Email & Accounts.

Tap the account you want to change.

Do any of the following:
Tap Download New
Content to change how often your phone checks for mail. You can download
mail instantly as it arrives or as seldom as every hour. You can also
turn off auto sync.
Tap Download Email From to change how many days’ worth of mail you download to your phone at once. The default is three days.
Under Content To Sync, tap a check box to select or clear it.
When you’re finished, tap Done.
