I created a new Silverlight 3 Application project today using Visual Studio 2008 and was surprised to see the following error –
‘Attempted to read or write protected memory. This is often an Indication that other memory is corrupt’
This seemed strange as I have created many Silverlight 3 apps before on the machine and never had any issues. After some research I realised that Windows might have automatically updated my installed version of Silverlight to Silverlight 4 which of course is not compatible with VS2008.
I looked in Programs & Features and this confirmed my fear – the installed version of Silverlight was 4.0.50524.0. See the screenshot below –
As you cannot use Silverlight 4 in Visual Studio 2010 you can either install VS2010 or you can downgrade your version of Silverlight back to 3. I chose to downgrade Silverlight. To do this you need to uninstall version 4 and then re-install version 3 which is located here – Silverlight 3 Tools.
Do not download and install the ‘Silverlight Runtime’ from the Microsoft Silverlight 3 site as this is the version 4 runtime.
After re-install Silverlight 3 – restart Visual Studio and you should now be able to see the XAML designer
Hope this helps!