The Take That star announced his official account details on The Xtra Factor last night, warning fans that any other social-networking account was fake.
"Let me tell you something, I have never ever been on Twitter," Barlow said. "So if anyone's been following me, it's not me."
Tulisa Contostavlos added: "There is a massive fake account of you, that has thousands of followers, that constantly tweet me!"
Posting his first tweet live on air, he wrote: "Hello everybody. This is my first tweet!"
In subsequent updates, Barlow said that he was "overwhelmed", adding: "Wow!!! Lots of you!! Welcome!"
The singer's follower count rose dramatically, with his tally crossing 265,000 this morning.
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