Seems like a bug started to do some exploit of it owns in Gmail system. As many as 500,000 Gmail users lost access to their inboxes, I am not one of them after checking out on the gmail account. I have been using outlook for years now, which has downloaded all my gmail mails.
Slashdot.org - Gmail Accidentally Resets 150,000 Accounts
“Many users have reported loss of their Gmail accounts, as they signed in to find their email accounts reset — losing years of email history. This appears to be a result of a bug which treats existing owners as new users. For those affected, Google is currently trying to resolve the problem. For the rest of us, perhaps this is a timely reminder to backup our data and be less trusting of the cloud.”
Update: No fix yet, but Google's revised its estimate as to how many users might have been affected by the issue -- "less than 0.08%" -- which means we're probably looking at closer to 150,000 individuals, rather than 500,000. We're assuming that the revised estimate means that the initial count wasn't precise, and not that customers are ditching Gmail in droves.
Update 2: Google's provided promising but terribly vague guidance on when the situation will be resolved: "Google Mail service has already been restored for some users, and we expect a resolution for all users in the near future. Please note this time frame is an estimate and may change."