You see the error message:
"The application has failed to start because it's side-by-side configuration is incorrect. Please see the application event log oruse the command-line sxstrace.exe tool for more detail."
When you try to install IBM Informix® product on Windows 2008 server.
This happens on computers which do not have Microsoft Visual C++ 2008 installed.
This is a issue with Windows 2008 and not with IBM Informix®.
Install all available Windows updates and the latest Windows service pack and check if this already solves the problem.
For more info, check out this link from Microsoft: http://support.microsoft.com/kb/2525435