If you attempt to install Back4, you may get the following error:

Installing assembly 'C:\Tera\GN4\bin\back4.exe'.

Affected parameters are:

   logtoconsole = 

   assemblypath = C:\Tera\GN4\bin\back4.exe

   logfile = C:\Tera\GN4\bin\back4.InstallLog

An exception occurred while trying to find the installers in the C:\Tera\GN4\bin\back4.exe assembly.

System.Reflection.ReflectionTypeLoadException: Unable to load one or more of the requested types. Retrieve the LoaderExceptions property for more information.

Aborting installation for C:\Tera\GN4\bin\back4.exe.

Rolling back assembly 'C:\Tera\GN4\bin\back4.exe'.

Affected parameters are:

   logtoconsole = 

   assemblypath = C:\Tera\GN4\bin\back4.exe

   logfile = C:\Tera\GN4\bin\back4.InstallLog

An exception occurred while trying to find the installers in the C:\Tera\GN4\bin\back4.exe assembly.

System.Reflection.ReflectionTypeLoadException: Unable to load one or more of the requested types. Retrieve the LoaderExceptions property for more information.

Aborting installation for C:\Tera\GN4\bin\back4.exe.

This might be due to the registering of DLLs in GAC on the Back4 server, but you missed to install GNClient.dll.

You can remove DLLs from GAC as explained in Unregistering DLLs in GAC for version 1.5 or newer on a GN4 server.

A better solution is add to the GAC also the GNClient.dll. See the instructions in Registering DLLs in GAC for version 1.5 or newer on a GN4 server