I am in the US on an L1 Blanket visa. I am an Indian. This is my first visit to the US and I arrived on the 17th of October 2006. I would be leaving the US on the 20th of April 2007. That makes my stay 185 days

I have already filed my Federal tax returns using the form1040EZ. I did it online using taxact.com website. Since I have never filed taxes in the US I have been asked to send the form 8453-OL. Also as per the form there is a tax refund which I have opted for direct deposit

As I was filing my State returns and I came to know about Full year Resident/Part year resident and Non resident status.

Have I filed the federal tax returns wrongly if yes what should I do?

Thanks

Yes, In my opinion you filed incorrectly. You should have filed as a non-resident alien.

You need to amend the return using Form 1040X and attach a correctly-prepared Form 1040NR-EZ with the word 'AMENDED' printed on top of the first page. Since you will not be able to claim the $5,150 standard deduction, expect to write a check to enclose with the amendment.