Here is the output of the installutil process:
Running a transacted installation.
Beginning the Install phase of the installation.
See the contents of the log file for the C:\users\Mark E. Schill\Documents\_Scripts\Core\Includes\IronCow\IronCow.Posh.dll assembly's progress.
The file is located at C:\users\Mark E. Schill\Documents\_Scripts\Core\Includes\IronCow\IronCow.Posh.InstallLog.
An exception occurred during the Install phase.
System.InvalidOperationException: Unable to get installer types in the C:\users\Mark E. Schill\Documents\_Scripts\Core\Includes\IronCow\IronCow.Posh.dll assembly.
The inner exception System.Reflection.ReflectionTypeLoadException was thrown with the following error message: Unable to load one or more of the requested types. Retrieve the LoaderExceptions property for more information..
The Rollback phase of the installation is beginning.
See the contents of the log file for the C:\users\Mark E. Schill\Documents\_Scripts\Core\Includes\IronCow\IronCow.Posh.dll assembly's progress.
The file is located at C:\users\Mark E. Schill\Documents\_Scripts\Core\Includes\IronCow\IronCow.Posh.InstallLog.
An exception occurred during the Rollback phase of the System.Configuration.Install.AssemblyInstaller installer.
System.InvalidOperationException: Unable to get installer types in the C:\users\Mark E. Schill\Documents\_Scripts\Core\Includes\IronCow\IronCow.Posh.dll assembly.
The inner exception System.Reflection.ReflectionTypeLoadException was thrown with the following error message: Unable to load one or more of the requested types. Retrieve the LoaderExceptions property for more information..
An exception occurred during the Rollback phase of the installation. This exception will be ignored and the rollback will continue. However, the machine might not fully revert to its initial state after the rollback is complete.
The Rollback phase completed successfully.
The transacted install has completed.
Running a transacted installation.
Beginning the Install phase of the installation.
See the contents of the log file for the C:\Users\Mark E. Schill\Documents\_Scripts\Core\Includes\IronCow\IronCow.Posh.dll assembly's progress.
The file is located at C:\Users\Mark E. Schill\Documents\_Scripts\Core\Includes\IronCow\IronCow.Posh.InstallLog.
An exception occurred during the Install phase.
System.InvalidOperationException: Unable to get installer types in the C:\Users\Mark E. Schill\Documents\_Scripts\Core\Includes\IronCow\IronCow.Posh.dll assembly.
The inner exception System.Reflection.ReflectionTypeLoadException was thrown with the following error message: Unable to load one or more of the requested types. Retrieve the LoaderExceptions property for more information..
The Rollback phase of the installation is beginning.
See the contents of the log file for the C:\Users\Mark E. Schill\Documents\_Scripts\Core\Includes\IronCow\IronCow.Posh.dll assembly's progress.
The file is located at C:\Users\Mark E. Schill\Documents\_Scripts\Core\Includes\IronCow\IronCow.Posh.InstallLog.
An exception occurred during the Rollback phase of the System.Configuration.Install.AssemblyInstaller installer.
System.InvalidOperationException: Unable to get installer types in the C:\Users\Mark E. Schill\Documents\_Scripts\Core\Includes\IronCow\IronCow.Posh.dll assembly.
The inner exception System.Reflection.ReflectionTypeLoadException was thrown with the following error message: Unable to load one or more of the requested types. Retrieve the LoaderExceptions property for more information..
An exception occurred during the Rollback phase of the installation. This exception will be ignored and the rollback will continue. However, the machine might not fully revert to its initial state after the rollback is complete.
The Rollback phase completed successfully.
The transacted install has completed.
Running a transacted installation.
Beginning the Install phase of the installation.
See the contents of the log file for the C:\Users\Mark E. Schill\Documents\_Scripts\Core\Includes\IronCow\IronCow.dll assembly's progress.
The file is located at C:\Users\Mark E. Schill\Documents\_Scripts\Core\Includes\IronCow\IronCow.InstallLog.
The Install phase completed successfully, and the Commit phase is beginning.
See the contents of the log file for the C:\Users\Mark E. Schill\Documents\_Scripts\Core\Includes\IronCow\IronCow.dll assembly's progress.
The file is located at C:\Users\Mark E. Schill\Documents\_Scripts\Core\Includes\IronCow\IronCow.InstallLog.
The Commit phase completed successfully.
The transacted install has completed.
Running a transacted installation.
Beginning the Install phase of the installation.
See the contents of the log file for the C:\Users\Mark E. Schill\Documents\_Scripts\Core\Includes\IronCow\IronCow.Posh.dll assembly's progress.
The file is located at C:\Users\Mark E. Schill\Documents\_Scripts\Core\Includes\IronCow\IronCow.Posh.InstallLog.
An exception occurred during the Install phase.
System.InvalidOperationException: Unable to get installer types in the C:\Users\Mark E. Schill\Documents\_Scripts\Core\Includes\IronCow\IronCow.Posh.dll assembly.
The inner exception System.Reflection.ReflectionTypeLoadException was thrown with the following error message: Unable to load one or more of the requested types. Retrieve the LoaderExceptions property for more information..
The Rollback phase of the installation is beginning.
See the contents of the log file for the C:\Users\Mark E. Schill\Documents\_Scripts\Core\Includes\IronCow\IronCow.Posh.dll assembly's progress.
The file is located at C:\Users\Mark E. Schill\Documents\_Scripts\Core\Includes\IronCow\IronCow.Posh.InstallLog.
An exception occurred during the Rollback phase of the System.Configuration.Install.AssemblyInstaller installer.
System.InvalidOperationException: Unable to get installer types in the C:\Users\Mark E. Schill\Documents\_Scripts\Core\Includes\IronCow\IronCow.Posh.dll assembly.
The inner exception System.Reflection.ReflectionTypeLoadException was thrown with the following error message: Unable to load one or more of the requested types. Retrieve the LoaderExceptions property for more information..
An exception occurred during the Rollback phase of the installation. This exception will be ignored and the rollback will continue. However, the machine might not fully revert to its initial state after the rollback is complete.
The Rollback phase completed successfully.
The transacted install has completed.
Running a transacted installation.
Beginning the Install phase of the installation.
See the contents of the log file for the C:\Documents and Settings\giy4\My Documents\Scripts\Core\Includes\IronCow\IronCow.Posh.dll assembly's progress.
The file is located at C:\Documents and Settings\giy4\My Documents\Scripts\Core\Includes\IronCow\IronCow.Posh.InstallLog.
An exception occurred during the Install phase.
System.InvalidOperationException: Unable to get installer types in the C:\Documents and Settings\giy4\My Documents\Scripts\Core\Includes\IronCow\IronCow.Posh.dll assembly.
The inner exception System.Reflection.ReflectionTypeLoadException was thrown with the following error message: Unable to load one or more of the requested types. Retrieve the LoaderExceptions property for more information..
The Rollback phase of the installation is beginning.
See the contents of the log file for the C:\Documents and Settings\giy4\My Documents\Scripts\Core\Includes\IronCow\IronCow.Posh.dll assembly's progress.
The file is located at C:\Documents and Settings\giy4\My Documents\Scripts\Core\Includes\IronCow\IronCow.Posh.InstallLog.
An exception occurred during the Rollback phase of the System.Configuration.Install.AssemblyInstaller installer.
System.InvalidOperationException: Unable to get installer types in the C:\Documents and Settings\giy4\My Documents\Scripts\Core\Includes\IronCow\IronCow.Posh.dll assembly.
The inner exception System.Reflection.ReflectionTypeLoadException was thrown with the following error message: Unable to load one or more of the requested types. Retrieve the LoaderExceptions property for more information..
An exception occurred during the Rollback phase of the installation. This exception will be ignored and the rollback will continue. However, the machine might not fully revert to its initial state after the rollback is complete.
The Rollback phase completed successfully.
The transacted install has completed.
Running a transacted installation.
Beginning the Install phase of the installation.
See the contents of the log file for the C:\Documents and Settings\giy4\My Documents\Scripts\Core\Includes\IronCow\IronCow.Posh.dll assembly's progress.
The file is located at C:\Documents and Settings\giy4\My Documents\Scripts\Core\Includes\IronCow\IronCow.Posh.InstallLog.
An exception occurred during the Install phase.
System.InvalidOperationException: Unable to get installer types in the C:\Documents and Settings\giy4\My Documents\Scripts\Core\Includes\IronCow\IronCow.Posh.dll assembly.
The inner exception System.Reflection.ReflectionTypeLoadException was thrown with the following error message: Unable to load one or more of the requested types. Retrieve the LoaderExceptions property for more information..
The Rollback phase of the installation is beginning.
See the contents of the log file for the C:\Documents and Settings\giy4\My Documents\Scripts\Core\Includes\IronCow\IronCow.Posh.dll assembly's progress.
The file is located at C:\Documents and Settings\giy4\My Documents\Scripts\Core\Includes\IronCow\IronCow.Posh.InstallLog.
An exception occurred during the Rollback phase of the System.Configuration.Install.AssemblyInstaller installer.
System.InvalidOperationException: Unable to get installer types in the C:\Documents and Settings\giy4\My Documents\Scripts\Core\Includes\IronCow\IronCow.Posh.dll assembly.
The inner exception System.Reflection.ReflectionTypeLoadException was thrown with the following error message: Unable to load one or more of the requested types. Retrieve the LoaderExceptions property for more information..
An exception occurred during the Rollback phase of the installation. This exception will be ignored and the rollback will continue. However, the machine might not fully revert to its initial state after the rollback is complete.
The Rollback phase completed successfully.
The transacted install has completed.
Running a transacted installation.
Beginning the Install phase of the installation.
See the contents of the log file for the C:\Documents and Settings\giy4\My Documents\Scripts\Core\Includes\IronCow\IronCow.Posh.dll assembly's progress.
The file is located at C:\Documents and Settings\giy4\My Documents\Scripts\Core\Includes\IronCow\IronCow.Posh.InstallLog.
An exception occurred during the Install phase.
System.InvalidOperationException: Unable to get installer types in the C:\Documents and Settings\giy4\My Documents\Scripts\Core\Includes\IronCow\IronCow.Posh.dll assembly.
The inner exception System.Reflection.ReflectionTypeLoadException was thrown with the following error message: Unable to load one or more of the requested types. Retrieve the LoaderExceptions property for more information..
The Rollback phase of the installation is beginning.
See the contents of the log file for the C:\Documents and Settings\giy4\My Documents\Scripts\Core\Includes\IronCow\IronCow.Posh.dll assembly's progress.
The file is located at C:\Documents and Settings\giy4\My Documents\Scripts\Core\Includes\IronCow\IronCow.Posh.InstallLog.
An exception occurred during the Rollback phase of the System.Configuration.Install.AssemblyInstaller installer.
System.InvalidOperationException: Unable to get installer types in the C:\Documents and Settings\giy4\My Documents\Scripts\Core\Includes\IronCow\IronCow.Posh.dll assembly.
The inner exception System.Reflection.ReflectionTypeLoadException was thrown with the following error message: Unable to load one or more of the requested types. Retrieve the LoaderExceptions property for more information..
An exception occurred during the Rollback phase of the installation. This exception will be ignored and the rollback will continue. However, the machine might not fully revert to its initial state after the rollback is complete.
The Rollback phase completed successfully.
The transacted install has completed.
Comments: ** Comment from web user: ludovic_chabant **
Running a transacted installation.
Beginning the Install phase of the installation.
See the contents of the log file for the C:\users\Mark E. Schill\Documents\_Scripts\Core\Includes\IronCow\IronCow.Posh.dll assembly's progress.
The file is located at C:\users\Mark E. Schill\Documents\_Scripts\Core\Includes\IronCow\IronCow.Posh.InstallLog.
An exception occurred during the Install phase.
System.InvalidOperationException: Unable to get installer types in the C:\users\Mark E. Schill\Documents\_Scripts\Core\Includes\IronCow\IronCow.Posh.dll assembly.
The inner exception System.Reflection.ReflectionTypeLoadException was thrown with the following error message: Unable to load one or more of the requested types. Retrieve the LoaderExceptions property for more information..
The Rollback phase of the installation is beginning.
See the contents of the log file for the C:\users\Mark E. Schill\Documents\_Scripts\Core\Includes\IronCow\IronCow.Posh.dll assembly's progress.
The file is located at C:\users\Mark E. Schill\Documents\_Scripts\Core\Includes\IronCow\IronCow.Posh.InstallLog.
An exception occurred during the Rollback phase of the System.Configuration.Install.AssemblyInstaller installer.
System.InvalidOperationException: Unable to get installer types in the C:\users\Mark E. Schill\Documents\_Scripts\Core\Includes\IronCow\IronCow.Posh.dll assembly.
The inner exception System.Reflection.ReflectionTypeLoadException was thrown with the following error message: Unable to load one or more of the requested types. Retrieve the LoaderExceptions property for more information..
An exception occurred during the Rollback phase of the installation. This exception will be ignored and the rollback will continue. However, the machine might not fully revert to its initial state after the rollback is complete.
The Rollback phase completed successfully.
The transacted install has completed.
Running a transacted installation.
Beginning the Install phase of the installation.
See the contents of the log file for the C:\Users\Mark E. Schill\Documents\_Scripts\Core\Includes\IronCow\IronCow.Posh.dll assembly's progress.
The file is located at C:\Users\Mark E. Schill\Documents\_Scripts\Core\Includes\IronCow\IronCow.Posh.InstallLog.
An exception occurred during the Install phase.
System.InvalidOperationException: Unable to get installer types in the C:\Users\Mark E. Schill\Documents\_Scripts\Core\Includes\IronCow\IronCow.Posh.dll assembly.
The inner exception System.Reflection.ReflectionTypeLoadException was thrown with the following error message: Unable to load one or more of the requested types. Retrieve the LoaderExceptions property for more information..
The Rollback phase of the installation is beginning.
See the contents of the log file for the C:\Users\Mark E. Schill\Documents\_Scripts\Core\Includes\IronCow\IronCow.Posh.dll assembly's progress.
The file is located at C:\Users\Mark E. Schill\Documents\_Scripts\Core\Includes\IronCow\IronCow.Posh.InstallLog.
An exception occurred during the Rollback phase of the System.Configuration.Install.AssemblyInstaller installer.
System.InvalidOperationException: Unable to get installer types in the C:\Users\Mark E. Schill\Documents\_Scripts\Core\Includes\IronCow\IronCow.Posh.dll assembly.
The inner exception System.Reflection.ReflectionTypeLoadException was thrown with the following error message: Unable to load one or more of the requested types. Retrieve the LoaderExceptions property for more information..
An exception occurred during the Rollback phase of the installation. This exception will be ignored and the rollback will continue. However, the machine might not fully revert to its initial state after the rollback is complete.
The Rollback phase completed successfully.
The transacted install has completed.
Running a transacted installation.
Beginning the Install phase of the installation.
See the contents of the log file for the C:\Users\Mark E. Schill\Documents\_Scripts\Core\Includes\IronCow\IronCow.dll assembly's progress.
The file is located at C:\Users\Mark E. Schill\Documents\_Scripts\Core\Includes\IronCow\IronCow.InstallLog.
The Install phase completed successfully, and the Commit phase is beginning.
See the contents of the log file for the C:\Users\Mark E. Schill\Documents\_Scripts\Core\Includes\IronCow\IronCow.dll assembly's progress.
The file is located at C:\Users\Mark E. Schill\Documents\_Scripts\Core\Includes\IronCow\IronCow.InstallLog.
The Commit phase completed successfully.
The transacted install has completed.
Running a transacted installation.
Beginning the Install phase of the installation.
See the contents of the log file for the C:\Users\Mark E. Schill\Documents\_Scripts\Core\Includes\IronCow\IronCow.Posh.dll assembly's progress.
The file is located at C:\Users\Mark E. Schill\Documents\_Scripts\Core\Includes\IronCow\IronCow.Posh.InstallLog.
An exception occurred during the Install phase.
System.InvalidOperationException: Unable to get installer types in the C:\Users\Mark E. Schill\Documents\_Scripts\Core\Includes\IronCow\IronCow.Posh.dll assembly.
The inner exception System.Reflection.ReflectionTypeLoadException was thrown with the following error message: Unable to load one or more of the requested types. Retrieve the LoaderExceptions property for more information..
The Rollback phase of the installation is beginning.
See the contents of the log file for the C:\Users\Mark E. Schill\Documents\_Scripts\Core\Includes\IronCow\IronCow.Posh.dll assembly's progress.
The file is located at C:\Users\Mark E. Schill\Documents\_Scripts\Core\Includes\IronCow\IronCow.Posh.InstallLog.
An exception occurred during the Rollback phase of the System.Configuration.Install.AssemblyInstaller installer.
System.InvalidOperationException: Unable to get installer types in the C:\Users\Mark E. Schill\Documents\_Scripts\Core\Includes\IronCow\IronCow.Posh.dll assembly.
The inner exception System.Reflection.ReflectionTypeLoadException was thrown with the following error message: Unable to load one or more of the requested types. Retrieve the LoaderExceptions property for more information..
An exception occurred during the Rollback phase of the installation. This exception will be ignored and the rollback will continue. However, the machine might not fully revert to its initial state after the rollback is complete.
The Rollback phase completed successfully.
The transacted install has completed.
Running a transacted installation.
Beginning the Install phase of the installation.
See the contents of the log file for the C:\Documents and Settings\giy4\My Documents\Scripts\Core\Includes\IronCow\IronCow.Posh.dll assembly's progress.
The file is located at C:\Documents and Settings\giy4\My Documents\Scripts\Core\Includes\IronCow\IronCow.Posh.InstallLog.
An exception occurred during the Install phase.
System.InvalidOperationException: Unable to get installer types in the C:\Documents and Settings\giy4\My Documents\Scripts\Core\Includes\IronCow\IronCow.Posh.dll assembly.
The inner exception System.Reflection.ReflectionTypeLoadException was thrown with the following error message: Unable to load one or more of the requested types. Retrieve the LoaderExceptions property for more information..
The Rollback phase of the installation is beginning.
See the contents of the log file for the C:\Documents and Settings\giy4\My Documents\Scripts\Core\Includes\IronCow\IronCow.Posh.dll assembly's progress.
The file is located at C:\Documents and Settings\giy4\My Documents\Scripts\Core\Includes\IronCow\IronCow.Posh.InstallLog.
An exception occurred during the Rollback phase of the System.Configuration.Install.AssemblyInstaller installer.
System.InvalidOperationException: Unable to get installer types in the C:\Documents and Settings\giy4\My Documents\Scripts\Core\Includes\IronCow\IronCow.Posh.dll assembly.
The inner exception System.Reflection.ReflectionTypeLoadException was thrown with the following error message: Unable to load one or more of the requested types. Retrieve the LoaderExceptions property for more information..
An exception occurred during the Rollback phase of the installation. This exception will be ignored and the rollback will continue. However, the machine might not fully revert to its initial state after the rollback is complete.
The Rollback phase completed successfully.
The transacted install has completed.
Running a transacted installation.
Beginning the Install phase of the installation.
See the contents of the log file for the C:\Documents and Settings\giy4\My Documents\Scripts\Core\Includes\IronCow\IronCow.Posh.dll assembly's progress.
The file is located at C:\Documents and Settings\giy4\My Documents\Scripts\Core\Includes\IronCow\IronCow.Posh.InstallLog.
An exception occurred during the Install phase.
System.InvalidOperationException: Unable to get installer types in the C:\Documents and Settings\giy4\My Documents\Scripts\Core\Includes\IronCow\IronCow.Posh.dll assembly.
The inner exception System.Reflection.ReflectionTypeLoadException was thrown with the following error message: Unable to load one or more of the requested types. Retrieve the LoaderExceptions property for more information..
The Rollback phase of the installation is beginning.
See the contents of the log file for the C:\Documents and Settings\giy4\My Documents\Scripts\Core\Includes\IronCow\IronCow.Posh.dll assembly's progress.
The file is located at C:\Documents and Settings\giy4\My Documents\Scripts\Core\Includes\IronCow\IronCow.Posh.InstallLog.
An exception occurred during the Rollback phase of the System.Configuration.Install.AssemblyInstaller installer.
System.InvalidOperationException: Unable to get installer types in the C:\Documents and Settings\giy4\My Documents\Scripts\Core\Includes\IronCow\IronCow.Posh.dll assembly.
The inner exception System.Reflection.ReflectionTypeLoadException was thrown with the following error message: Unable to load one or more of the requested types. Retrieve the LoaderExceptions property for more information..
An exception occurred during the Rollback phase of the installation. This exception will be ignored and the rollback will continue. However, the machine might not fully revert to its initial state after the rollback is complete.
The Rollback phase completed successfully.
The transacted install has completed.
Running a transacted installation.
Beginning the Install phase of the installation.
See the contents of the log file for the C:\Documents and Settings\giy4\My Documents\Scripts\Core\Includes\IronCow\IronCow.Posh.dll assembly's progress.
The file is located at C:\Documents and Settings\giy4\My Documents\Scripts\Core\Includes\IronCow\IronCow.Posh.InstallLog.
An exception occurred during the Install phase.
System.InvalidOperationException: Unable to get installer types in the C:\Documents and Settings\giy4\My Documents\Scripts\Core\Includes\IronCow\IronCow.Posh.dll assembly.
The inner exception System.Reflection.ReflectionTypeLoadException was thrown with the following error message: Unable to load one or more of the requested types. Retrieve the LoaderExceptions property for more information..
The Rollback phase of the installation is beginning.
See the contents of the log file for the C:\Documents and Settings\giy4\My Documents\Scripts\Core\Includes\IronCow\IronCow.Posh.dll assembly's progress.
The file is located at C:\Documents and Settings\giy4\My Documents\Scripts\Core\Includes\IronCow\IronCow.Posh.InstallLog.
An exception occurred during the Rollback phase of the System.Configuration.Install.AssemblyInstaller installer.
System.InvalidOperationException: Unable to get installer types in the C:\Documents and Settings\giy4\My Documents\Scripts\Core\Includes\IronCow\IronCow.Posh.dll assembly.
The inner exception System.Reflection.ReflectionTypeLoadException was thrown with the following error message: Unable to load one or more of the requested types. Retrieve the LoaderExceptions property for more information..
An exception occurred during the Rollback phase of the installation. This exception will be ignored and the rollback will continue. However, the machine might not fully revert to its initial state after the rollback is complete.
The Rollback phase completed successfully.
The transacted install has completed.
Comments: ** Comment from web user: ludovic_chabant **
That's weird, I installed it on several computers without problems...
From the looks of this error, though, you're missing some of the dependencies of IronCow.Posh.dll. Maybe you don't have the old DLLs sitting next to it? (IronCow.dll and PoshBuild.dll)