What actors and actresses appeared in The Happiest Day of His Life - 2007?

You're likely thinking of the movie "The Happiest Day of Our Lives" (2011), not "The Happiest Day of His Life".

The film features:

* Sushant Singh Rajput as Akash

* Ileana D'Cruz as Ananya

* Mohnish Bahl as Rajesh

* Rituparna Sengupta as Manisha

* Asif Basra as Raghu

* Divya Dutta as Shabnam

* Anupam Kher as Aakash's father

* Neena Gupta as Aakash's mother

* Dimple Kapadia as Aakash's aunt

* Nasseruddin Shah as Aakash's lawyer

Please note that there is no movie called "The Happiest Day of His Life" released in 2007.