What is the envelope with an explanation point next to it mean on mytouch 4G phone?

The envelope icon with an exclamation point on your myTouch 4G phone typically indicates that you have received a new email or message, but there may be an issue with syncing or retrieving it. This could be due to a connection problem or an issue with your email settings. It's a good idea to check your email application for any alerts or notifications to resolve the issue.