problem with PDFNet.dll on production server

I am using PDFNet.dll to convert PDF to XOD in a function within one
of my DLLs. This DLL is then used in my web project where I am using
silverdox to show the XOD document served by this web site. This works
great on my dev box but when I move the project in production PDFNet
fails. My dev machine is Win7 running IIS 7.5. The production box runs
Win Server 2008 R2 also running IIS 7.5. I did a file by file compare
including the web.config and they are identical yet the problem exists
in production. PDFNet fails differently when I use the .NET 4.0
version versus the 1.0 - 3.5 one. I first tried the .NET 4.0. When I
use it, it takes the whole site down on any page request with IIS
complaining that it can't load PDFNet.dll. So then I thought I would
try the 1.0 - 3.5 PDFNet. This one does not take the sever down but
throws an exception during the PDF to XOD conversion. Any ideas what
could cause this expecialy that my dev box works perfectly.

The most likely problem is that:

a) The DLL version (32 vs 64 bit) does not match your project solution. For example you are using 32 bit DLL in 64 bit project or the other way around. For more info please see

b) Your target machine is missing standard VC redistributable. For more info see

Q: My dev machine is 32 bit Win 7 while the prod machine is Win Server
2008 R2 which is 64 bit. What is the best way to handle this discrepancy for deployment and how can I streamline the development?

A: You could use 32 bit version of PDFNet on both systems. In this case in your IIS 2008 R2 Web Server application pool, set the Identity to “LocalSystem” (for both .NET 2.0 and .NET 4.0). Also, make sure to set the “Enable 32-Bit Applications” to “True”.