With Reader 9.3.1 updated directly from Adobe's website, our custom application that batch prints PDF files works correctly. However, when our Client Support team built the installer with Adobe's tools to update our users, the same custom application does not print the files. I'm not able to trap any errors when I issue the print call. It essentially has the registered application for that file type print the file. My app thinks that it prints but the printer never appears in the System Tray and never prints.
My guess is that there is some difference in the registry entries when installed from Adobe's site versus using the Adobe installer. I haven't been able to detect which entry might be causing the problem.
We're a large corporation so manually installing the 9.3.1 version at each PC is not a good option.