You must meet the prerequisites for courses by taking the listed prerequisite or a similar approved course.  If you believe you have taken a course that meets the prerequisites for the course you would like to register for and you cannot get in, you should contact the department offering the course to see what options you have.  The location of departments can be found in the OSU Catalog or Schedule of Classes course descriptions; by searching for and viewing the department web page on the OSU website; or by calling Campus Information at 541-737-0123 and asking for them.  Some links to department with common override issues are listed below.