InstallAware

Our setup won't run properly on a Windows 2008 R2 computer.
SQL Server 2008 R2 is installed and it updated the .NET 2 framework.

Now we run our setup with a .NET 2 prerequisite and it confuses the version (newer than expected) with the one it like's to have, so we get the message to upgrade Microsoft .NET Framework 2.0 (x64) (which is included in the setup)

When we run the upgrade, from within our setup we get the message:

Microsoft .NET Framework 2.0 (x64) could not be installed. The Windows Installer Service could not be accessed. This can occur if the Windows Installer is not correctly installed. Please use Windows Update to manually install this update on your system. The Setup cannot continue.

So we do try the manual installation of the setup and ofcourse we get the message:

This product is alreay installed as part of the operating system.

We use the second release of your latest version (InstallAware 9).
Now is my question, how do we make sure the setup will continue, creating a new setup is not an option

What version is installed? You should be able to find out by the version folder in:

C:\Windows\Microsoft.NET\Framework64

version 2.0.50727 is installed
How does the installer check if it is installed, maybe there is a way to "trick" it by adding a registry value

I can't reproduce this.

Can you post a sample project that exhibits this problem?