F Visa

I came to the US on a B1 visa got it changed to F1-->finsihed 4 years of undergrad moved on to 2 years of Masters(both in engineering). I am yet to apply for OPT. Is this going to affect my chances due to the entry method; also what will happen if I get a company that want to sponspor me. Would you advise me to go back home to rectify my visa situation. Because the B1 visa I entered the country with is expired, I haven't travelled out of the country. What would you suggest I proceed about this.I really would love to go back home to visit but scared the consulate will deny me.
Confused as ever.

I'm a H.S Senior student, I have studied all my school year in the U.S but Iam a citizen of Mexico, can I receive a student visa while in the U.S?

My OPT started on September 16th, 2009 and I don't have job or job offer yet. But I need to travel outside the USA for 1 week. I talked to the International Adviser of my University and she told me its fine to travel no problem. I don't still feel safe. Can anybody answer whether I will be allowed to enter or not? I have other documents.

I'm a permanent resident and I would like to know if I could sponsor my daughter who is over 21 and is currently on F1 status. If so, would she be allowed to stay in the U.S. if her visa expires during processing?
How long will this process take.

Can I work in the campus of the school with F-2 visa?

After studying a 1 year graduate course in the US. Would I qualify for a work permit? Or would I still have to find an employer to sponsor me first before I could apply for the work permit?

I got a 2 year visa for my Masters and my Visa was expired on May 31st 2009, I converted to OPT from June 1st, 2009. I am on OPT and I do have a job now. I got an emergency now to go to India. Is it possible for me to reenter United States.

I currently have both an B1/B2 and F1 visa. I got into a graduate program at a university in Teaneck, New Jersey. What are the possibilities of getting a job off campus and would i be able to get a social security card..? What are the issues i have to deal with in such cases?

I have a small query that F-1 student are allowed to work on-campus(20 hr) and for off-campus they need work permit but if they solve quetsions over internet and get paid by someone outside US then is it legal? or does it require any permit? In other words if some student (F1) provide support to some company outside USA (over internet) and get paid is it legal?

I was just wondering what the laws say about an F-1 student working for the company that he co-founded when he's on OPT. Suppose that I start up a new business while I'm still a full time student, I can't draw a salary from it but I maintain ownership, in part or whole. When I'm done with school, and approved for my OPT, can I work at my company and draw a salary from it then?