Gmail has been down since 4 pm ET on Tuesday, September 1.

The Google Apps Status Dashboard is showing a service outage. At the time this article was filed, trying to visit returned a server error.

Google said that the problem was affecting so many of its customers that it decided to also notify users on the Gmail Blog.

Engineering director David Besbris said the problem was a minor issue, and gave no further information on what may have caused the outage.

We are continuing to investigate this issue. We will provide an update by September 1, 2009 5:16:00 PM UTC-4 detailing when we expect to resolve the problem, Google latest status update reads.

We’re terribly sorry for the inconvenience and will get Gmail back up and running as soon as possible, he said.

Last month, Google's Gmail has surpassed AOL as the third most visited e-mail service in the U.S.