1. On the Tools menu, click E-mail Accounts.
2. Click View or change existing e-mail accounts, and then click Next.
3. Select your ISP account, and then click Change.
4. Click More Settings.
5. Click the Advanced tab, and under Delivery, select the Leave a copy of messages on the server check box.

• • Remove from server after x days   E-mail messages are downloaded to your computer but remain on the e-mail server for the number of days that you specify. This is the most common setting for people who want to read their messages at work but also download them for permanent storage on their home computer. We recommend that you choose the smallest number of days that suits your needs. The longer you leave messages on your e-mail server, the greater the risk of exceeding your mailbox size quota.
  • Remove from server when deleted from 'Deleted Items'   E-mail messages are downloaded to your computer but also remain on the e-mail server indefinitely until you delete the e-mail message in Outlook and empty the Deleted Items folder. Just deleting the message doesn't remove the message from the e-mail server.

  If you do not select either check box, messages are left on the server indefinitely. You can eventually exceed your mailbox quota, unless you connect to the e-mail server from another computer that has Outlook configured to remove messages from the e-mail server.

Click OK, and then click Finish.