During the installation of Expression Web 3, you may encounter the following error:

Exception has been thrown by the target of an invocation.Cannot find DependencyProperty or PropertyInfo for property named ‘Effect’. Property names are case sensitive. Error at object ‘LayoutRoot’ in markup file ‘XSetupUI;component/initializationwindow.xaml’.

Clicking the OK button takes you out of the installation and there you are – no Expression Web 3 installed on the machine and you feeling pretty frustrated. What blocksdoes that error even mean anyway?

In a nutshell, that error means you have a bad install of the .NET Framework 3.5 SP1 on the machine, which is required for both the setup of Expression Web 3 and the program itself to run. To resolve it, do the following:

If you are running Windows XP or Windows Vista:

1. Click START > Control Panel > Programs and Features

2. Locate “Microsoft .NET Framework 3.5 SP1” in the list. Right click it and left click on “Uninstall”. This should uninstall the Framework.

3. Please reinstall the .NET Framework 3.5 SP1 – you can download and install it from the Microsoft .NET Framework 3.5 SP1 Download Page

4. Once the reinstall of the .NET Framework 3.5 SP1 is finished, try installing Expression Web 3 again.

If you are running Windows 7:

1.    Click START > Control Panel and on the left, click “Turn Windows Features on or off” and when the “Windows Features” menu comes up, uncheck the main box for Microsoft .NET Framework 3.5.1 and then click OK. It will take a few moments to make the changes.

2.    Then go back to “Turn Windows Features on or off” and when the “Windows Features” menu comes up, select the main box for Microsoft .NET Framework 3.5.1. It will not have a check – it should have a filled in box - and then click OK. It will take a few moments to make the changes. Afterward, try installing Expression Web 3 again.