official letter

Can i starta officail letter with" how are u " if i am writing it to a person who i have earlier worked with and reapproaching for the same position again

[eccampbell]

No, you may not start an official letter with "how are u." Always use proper capitalization, such that every sentence begins with a capital (upper case) letter, and NEVER abbreviate "you" to "u" in an official letter -- yuck, barf-o, zilchareenie.

[Ouisch]

Even "How are you?" is too informal for an official letter. You could, however, open with "I hope this letter finds you well."