Google underestimated the scope and consequences of the outage that hit Gmail on Tuesday.
In its latest update about the problem, Google said that the hour-plus-long outage affected "less than 10 percent" of Gmail's user base, much more than the original estimate of "less than 2 percent."
Moreover, in that update posted at around 9:45 p.m. U.S. Eastern Time, Google also warned about possible lingering effects stemming from the outage.
"While we have resolved this issue with Google Mail, it's possible that some users may experience message delays because affected accounts weren't available to receive messages. The messages will be successfully delivered after account access is restored," the note in the Google Apps Status Dashboard reads.
Assuming that 9.5 percent of Gmail users were affected, that would mean that the problem hit about 33.2 million people. Gmail has more than 350 million active users.
"What this Gmail outage underscores is the massive reach of public portal email. While the vendor might blithely say -- 'oh, only 2% of our users are affected' -- the reality is that the small percentage translates to millions of customers being left without service," said Gartner analyst Matthew Cain via e-mail.
Google first acknowledged the problem at about 12:40 p.m. on Tuesday, and said it had been resolved at around 1:45 p.m.
In the Apps Status Dashboard notes, Google also apologized "for the inconvenience," thanked Gmail users for their "patience and continued support" and said that it is continually making improvements to its "system reliability," which the company considers "a top priority."
Gmail is used by individuals for personal matters and by companies for employee communications as part of the Google Apps cloud-hosted collaboration and communication suite.
Juan Carlos Perez covers enterprise communication/collaboration suites, operating systems, browsers and general technology breaking news for The IDG News Service. Follow Juan on Twitter at @JuanCPerezIDG.