Bonsoir J avais le meme pb que vous, j ai trouvé la solution sur un site americain, et ça marche nickel ! suivre cette procedure Thank you for choosing Autodesk Support. Thank you for choosing Autodesk Support. I understand when exporting to PDF you are receiving >an "Internal Error: Null Pointer" error. We have noticed that this error can occur when the PDF PC3 file from AutoCAD 2009 is, somehow, used in AutoCAD 2010. In the AutoCAD 2010 Options (Type OPTIONS in the command line), click the "Files" tab, expand "Printers Support File Path," and then >expand the "Printer Configuration Search Path. The path should look like the one below, pay particular attention to the 2010 near the end of >the string: C:\Documents and Settings\\Application Data\Autodesk\AutoCAD 2010\R18.0\enu\Plotters If 2009 appears where 2010 should be then use the "Browse" button to set the path correctly. If the Path is set correctly and this error still occurs, then use the "Add a plotter wizard" to re-create the PDF PC3 driver: If the Path is set correctly and this error still occurs, then use the "Add a plotter wizard" to re-create the PDF PC3 driver: 1. On the Command line type plottermanager, and then press the Enter key. 2. Open the "Add a Plotter Wizard" 3. Click on the "next" button. (My Computer should be selected by default.) 4. Under "Manufactures", choose "Autodesk ePlot (PDF). 5. Under "Model", choose PDF. 6. Click on the "Next" button 3 (three) more times. 7. Type DWG to PDF for the name., 8. Click on the "Next" button. 9. Click on the "Finish" button. In most of the earlier instance this has resolved the issue if it doesn’t I suggest perfuming a repair installation of AutoCAD 2010 from add and >remove programs. JF