Here is a note from the Mentor Graphics SupportNet site. (I work for Mentor.) Michael Holley www.swtpc.com/mholley Adobe Acrobat Reader 6.0 Issue There is a bug within Acrobat 6 which causes SupportNet incompatibility. This issue was identified by Adobe as a known issue with the Acrobat Reader 6.0. This version of the reader is not capable of handling the HTTP headers generated by the SupportNet security system. Solution 1: Save the PDF file to your hard drive, and open it in Adobe Acrobat or Adobe Reader. 1. Right-click the link to the PDF file on the Web site, and then choose Save Target As (Internet Explorer) or Save Link As (Netscape Navigator) from the pop-up menu. 2. In the Save As dialog box, select a location on the hard disk, and then click Save. 3. Double-click the PDF file to open it in Adobe Acrobat or Adobe Reader. Solution 2: Disable Web Browser Integration. 1. In Acrobat or Adobe Reader, choose Edit > Preferences > Internet. 2. Deselect Display PDF in Browser, and then click OK. Solution 3: Use Acrobat 5.x. Remove Acrobat 6.0 or Adobe Reader 6.0, and then install Acrobat 5.x. You can download the free Acrobat Reader 5.1 from the Adobe Web site at www.adobe.com/products/acrobat/alternate.html