The actress says the original 2011 film will always be "memorable" for her as it turned out to be a stepping stone in her career.
"I got 'Tanu Weds Manu' at a time when I didn't have much projects in my hand and I was struggling to make myself known in the industry. The film was an unexpected hit at that time. The film will forever be close to my heart," said Kangana, who was joined by the whole cast of the film.
The team at the event on Monday included R. Madhavan, Jimmy Shergill, Deepak Dobriyal, Swara Bhaskar and Eijaz Khan. Also present were director Anand L. Rai, producer Krishika Lulla and writer Himanshu Sharma.
Talking about Anand L. Rai, Kangana, who plays the role of Tanu in the film, said: "I've shared a special relationship with all my directors. But if I talk about Anand ji, he gave me a platform at a time when I was nobody."
Asked why it was decided to launch the new film's poster on her birthday, the Himachali girl said: "It was a co-incidence actually. We were planning a party in Mumbai. But then the film's release date was preponed. The film was supposed to release in June. But now it will release in May. Anand ji suggested releasing the poster on my birthday.
"I'm very happy. Unlike the usual birthday plans, I'm thrilled to promote 'Tanu Weds Manu Returns' as it is really special for me. The film depicts the real life of a husband and wife which viewers have hardly seen in Bollywood. The intensity and humour used to reveal the contemporary and complex relationship in this film is very special."
As the film focuses on marriage and it's after effects, a specially decorated stage -- like those in weddings -- was set up at the event.
Although Kangana is playing a married woman in the film, the "Gangster" actress has no intentions to settle down in her real life as of now.
"The one percent eagerness that I used to have about marriage is gone after looking at this film. People will get shocked after viewing the ruined life of Tanu and Manu. After this film, I have gone back to my happily single days," she quipped.
Madhavan will be seen in his role as Manu again in the film, which is currently being shot in Delhi.
Director Anand L. Rai said: "It rarely happens that you get a chance to work with the same cast of a film again. It's like coming back to home for me."
"Tanu Weds Manu Returns" is slated to release in end of May.