Some customers have reported issues in launching Expression Interactive Designer where it crashes on launch. This issue has been documented here. These problems have since been addressed by the WPF team. While there is no known workaround for the non-Intel P4 chipset issue, there is some twiddling that you could do to workaround the corrupt GAC bug. If you are interested in doing this (and I really hope you are since I would love to hear more feedback about the product from you), you can do the following:

 

Step 1: Making sure it is the same issue

  1. Download a tool (small .exe) that I wrote from here. Rename CustomAssemblyAttributeDebugger.exe.zip to CustomAssemblyAttributeDebugger.exe
  2. After copying the tool locally, run it. If you get some debug output in your command prompt (not just “Hit any key to finish..”), you know that it is the same issue. The tool will also tell you what the problematic assemblies installed in your GAC are. What is happening is that these assemblies define some attributes that reference types that are not defined in any of the assemblies currently in the GAC. This really is the root cause of the WPF issue. This is likely caused by some installer that did not clean up correctly and left things in the GAC whereas it should not have.

Step 2: Fixing the issue

  1. To fix the issue, there are two steps that you can take. First option is to re-install the assemblies that define the missing types.
  2. Install on a cleaner machine, or clean up the erroneous assemblies in the GAC listed by the tool you tried. Unfortunately, I don't have enough experience with the latter approach but you can find a lot of information here at http://msdn.microsoft.com/library/default.asp?url=/library/en-us/cptools/html/cpgrfglobalassemblycacheutilitygacutilexe.asp