Google acknowledged that Gmail had a widespread, worldwide collapse shortly before 4 p.m. U.S. Eastern Time on Tuesday and declared the outage resolved at close to 5:40 p.m., according to information posted on the .

In that dashboard, Google offers performance and availability information about the online services included in its Apps collaboration and communication suite, such as Gmail, Calendar, Talk, Docs and Sites.

Tuesday afternoon's outage officially lasted about 1 hour and 45 minutes. "During that period, users could continue to send and receive e-mail using POP and IMAP," a Google spokesman said via e-mail.

Google is investigating the cause of the outage and hopes to share its findings soon, Google engineering director David Besbris said in an .

The outage followed another of a smaller scale at mid-afternoon Monday that apparently wasn't fully solved until late Tuesday morning.