I have PAF-5, PAF Companion v. 5.1.5 and Acrobat Reader v.7 installed on my computer running Win XP Home SP2. Each of the programs works fine separately. However, when I try to Preview chart in the Descendant Chart Options of the Companion, I'm getting an error message: <PDF Viewer. We were unable to locate a default PDF viewer...> What's going wrong? Why PAF Comp cannot find Acrobat Reader on my hard drive? I tried to open Acrobat before Companion, but it didn't help... May someone please help me to fix this problem. Ilya Zeldes Fort Myers, Florida