MOUNTAIN VIEW, Calif. (

TheStreet

) --

Google

(GOOG) - Get Report

is expanding its "Gone Google" advertising campaign Monday to attract customers to its online office software.

On the company blog on its Web site, Google said Monday it is "excited to support this global momentum with the expansion of the 'Gone Google' initiative to additional countries including the U.K., France, Canada, Japan, Australia and Singapore. We hope our messages ... help companies, schools and organizations learn all about the benefits of going Google with our enterprise products."

Google said more than 2 million businesses and 20 million users now use Google Apps for their workplaces.

Reuters

reports Google's move is a rare foray into mass-market advertising and underscores increasing competition to provide businesses with email and other office software.

Microsoft

(MSFT) - Get Report

and

IBM

(IBM) - Get Report

dominate the market for enterprise email, but Google is trying to convince businesses to switch to its so-called cloud-based services, in which software is accessed over the Internet and maintained at Google's data centers instead of on a company's computers,

Reuters

notes.

Google is expected to run ads in major newspapers and magazines, as well as on billboards in airports and train stations,

Reuters

says.

-- Reported by Joseph Woelfel in New York

.

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