On Monday, Gmail users across the US, Canada and India reported that they were having problems getting access to the email system.
At the same time, ironically, Google's own staff were having issues with, Reuters says, a Google employee also reporting that the company's own corporate e-mail account was down.
Google says that it has now resolved the problems and explains that it was an issue with its contacts system.
An outage in the contacts system used by Gmail prevented the e-mail system from loading properly.
Gmail users started having problems accessing their emails online at about 5pm EDT.
An announcement on the company's Gmail "Help Center" site says that the issue is now resolved, but the web company added that there may be minor delays in deliveries even though all mail is safe.