Hi!! I applied for study VISA in Germany on 30/07/2010. I received my VISA today but they have made a strange & stupid mistake. My type of VISA is 'D' but my duration of stay is 90 days. My classes start on 1st October, 2010. I am a Pakistani National as pf now. So how do I get this issue resolved?
Contact the ambassy or consulate that issued the visa immediately; there may be some action you need to take prior to leaving for Germany, I don't know. Worst case scenario is that you need to re-apply; but I think it's more likely they will tell you to ask for an extension immediately after you've arrived in Germany. Don't take my word for any of this, though; make inquiries with the authorities.