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Yahoo Inc. is redesigning its email service to help stem a user decline and counter offerings from longtime rivals Microsoft Corp. and Google Inc. as well as social-networking services such as Facebook and Twitter.

The planned changes to Yahoo Mail, part of a project codenamed "Minty," are aimed partly at increasing the speed of the service in overseas markets where Internet connections are slower than in countries such as the U.S.

Yahoo is also changing the look of the service to resemble the simpler design of the email app that is downloaded on mobile devices such as Apple Inc.'s iPad or phones that use Google's Android software. The updates to the email service are expected to roll out this fall.

Yahoo executives earlier this year mentioned the planned redesign to financial analysts and application developers, a company spokesman said, but the project received little attention.