Hi

I am an F1 student and have filed 1040 instead of 1040NREZ.
What should I do now?

Confused Desi

You must file amended tax return Form 1040X along with your nonresident tax return.

About nonresident filing read: Read: Your U.S. Tax Return: U.S. Tax Filing Requirements for Non-Residents (http://taxipay.blogspot.com/2008/03/us-tax-filing-requirements-for-non.html)