Follow the steps below to change the frequency that your e-mail software checks for and advises you of new e-mail messages.

Adjust Frequency of Incoming E-mail Pick-ups in Outlook Express When Using Windows XP:
1. With Outlook Express open, click your cursor arrow on "Tools" located on the menu bar and select "Options" from the drop-down menu.
2. When the "Options" window appears, click on the "General" tab.
3. Under "Send/Receive Messages," look for the check boxes next to "Play sound when new messages arrive" and "Check for new messages every (# of minutes) minute(s)." If you want to turn off the alert sound, uncheck its check box. If you want to change the frequency of mail pick-ups, either uncheck its check box or change the number of minutes between pick-ups to a more suitable number.
4. Click on the "Apply" button and click "OK" to close the window.
Adjust Frequency of Incoming E-mail Pick-ups in Outlook When Using Windows XP:
1. With Outlook open, click your cursor arrow on "Tools" located on the menu bar. Drop down to "Send/Receive" from the drop-down menu and then "Send/Receive Settings" from the resulting submenu. Then choose "Define Send/Receive Groups" from the next submenu. Or, if that sounds too complicated, press on the "Ctrl" + "Alt" + "S" keys.
2. When the "Send/Receive Groups" window appears, select the groups you want to modify in the "Group Name" field or just select "All Accounts" to make your changes global.
3. Look for settings for the group "All Accounts" or the name of the group you selected and then look for the check box next to "Schedule an automatic send/receive every (# of minutes) minutes." Change the time in the field to whatever amount of time seems reasonable.
4. Click on the "Close" button to close the "Send/Receive Groups" window.
Adjust Frequency of Incoming E-mail Pick-ups in Thunderbird 1.0.7 When Using Windows XP and Thunderbird 1.5 on Mac OS X:
1. With Thunderbird open, click your cursor arrow on "Tools" located on the menu bar and drop down to "Account Settings" from the resulting drop-down menu.
2. When the "Account Settings" window opens, click on your account name in the pane on the left side and, if it has a small "+" (plus sign) next to it, expand it by clicking on it.
3. Click on "Server Settings."
4. Under "Server Settings," look for "Check for new messages every (# of minutes) minutes." Adjust the number of minutes in the field to whatever amount of time seems reasonable.
5. Click "OK."
Adjust Frequency of Incoming E-mail Pick-ups in Netscape 7.2 When Using Windows XP and Mac OS X:
1. With Netscape Mail open, click your cursor arrow on "Edit" located on the menu bar and drop down to "Mail & Newsgroups Account Settings" from the resulting drop-down menu.
2. When the "Account Settings" window opens, click on your account name in the pane on the left side. If the arrow next to the account name is pointing to the right, click on it so that it points down and expands to show the server settings.
3. Click on "Server Settings."
4. Under "Server Settings," look for "Check for new messages every (# of minutes) minutes." Adjust the number of minutes in the field to whatever amount of time seems reasonable.
5. Click "OK."
Adjust Frequency of Incoming E-mail Pick-ups in Mail.app 2.0 When Using Macintosh OS X:
1. With Mail.app open, click your cursor arrow on "Mail" located on the menu bar and select "Preferences" from the drop-down menu.
2. Click on the "General" button on the button bar at the top of the window.
3. Find the item labeled "Check for new mail:" and set the interval by clicking on the menu to the right.
4. Click the red dot in the upper left hand corner of the window to close it.
Adjust Frequency of Incoming E-mail Pick-ups in Entourage 2004 When Using Macintosh OS X:
1. With Entourage open, click your cursor arrow on "Tools" located on the menu bar and select "Schedules" from the drop-down menu.
2. Find the schedule named "Send and Receive all" and double click on it.
3. When the "Edit Schedule" window opens, click on the button under the heading "When" and select the time interval that seems best to you.
4. Click "OK" to close the window.

(SOURCE: The Home front Reporter Team