Microsoft Outlook supports the IMAP4 protocol. Some servers may use an updated standard called IMAP4rev1, which may prevent authentication of your credentials and access to your account. To verify which IMAP protocol your server is using, contact your system administrator or Internet service provider (ISP).

Microsoft Outlook might be displaying only the folders you subscribed to.

1. On the Tools menu, click IMAP Folders.
2. Clear the When displaying hierarchy in Outlook, show only subscribed folders check box.

You might be in a view that does not show deleted messages.

• On the View menu, point to Arrange By, point to Current View, and then click Group Messages Marked for Deletion.

IMAP does not support message flags, so you cannot send or receive messages with flags on them. You can set flags on messages that stay in your Inbox or in another folder, for example, to remind you to follow up.

You are viewing messages that have only headers downloaded. You need to download the body of the message.

Any rules you have set up to work on text in the body of a message will not work for IMAP messages that have only headers downloaded. You need to download the entire message for the rule to work.