This is in the end of your ASP.NET error message:
Version Information: Microsoft .NET Framework Version:v1.1.4322;
Wrong ASP.NET version is configured for the virtual directories in IIS. Every IIS-virtual site is configured to use some particular version of .NET Framework. AxCMS.net Version 5.5.0 and above uses .NET Framework 2.0, versions like 5.2.x and below use .NET Framework 1.1.
To configure the .NET Framework version go to IIS, click Properties for the website and in tab ASP.NET check the version there. Do that for all virtual directories as well.
Read here more about configuring IIS: http://en.help.axinom.de/en_help_cms_inst_iis.AxCMS
AxCMS.net versions: All versions