I would definitely let them know about your previous college experience. Most colleges have a place on the application where you can give information about extenuating circumstances and things they should know about you. Worse comes to worse you may need to take one semester to prove yourself or they may accept you into an associates program which you can trasnfer out of after a semester or two. Just keep the big picture in mind. There is something which you should ask about though. If the college accepts the credits from your previous college you should ask if you can get your GPA adjusted so the unsatisfactory grades wont hurt your current GPA. UNH will do this if you have been out of school for at least 5 years. As long as your grades are passing you get the credit but the grades aren't counted against your GPA. Usually you have to request this BEFORE you start classes but you may be able to ask for a policy variance if you have already started. Hope this helps.
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Anne Marie Olsen
Non-Traditional Student Organization
University Of New Hampshire