This is why the student and paid version are different...
Quote "Student versions
AutoCAD is licensed at a significant discount over commercial retail pricing to qualifying students and teachers, with a 36-month license available. The student version of AutoCAD is functionally identical to the full commercial version, with one exception: DWG files created or edited by a student version have an internal bit-flag set (the "educational flag"). When such a DWG file is printed by any version of AutoCAD (commercial or student), the output includes a plot stamp / banner on all four sides. Objects created in the Student Version cannot be used for commercial use. Student Version objects "infect" a commercial version DWG file if imported."ENDQUOTE
All the best Brett