CS0587 compiler error during XAML IMPORT/PARSE step

[azerty]

Hello,

I try compil an very simple "Hello world WPF application" with a VSTS
2008

And I have this error :

Error 1 Internal Compiler Error (0xc0000005 at address 0045E073):
likely culprit is 'IMPORT'. E:\Fichiers\Dev\Research\Test
\WpfApplication\CSC WpfApplication
Error 2 Internal Compiler Error: stage 'IMPORT' c:\Program Files
\Reference Assemblies\Microsoft\Framework\v3.5\System.Core.dll
WpfApplication
Error 5 stage 'BEGIN' E:\Fichiers\Dev\Research\Test\WpfApplication
\error CS0587 WpfApplication
Error 3 stage 'IMPORT' E:\Fichiers\Dev\Research\Test\WpfApplication
\error CS0587 WpfApplication
Error 4 stage 'PARSE' E:\Fichiers\Dev\Research\Test\WpfApplication
\error CS0587 WpfApplication

I just found the initial problem, If I have include a xmlns
declaration in a XAML file like this

xmlns:fr="clr-namespace:myNameSpace" (IMPORTANT :
without ;assembly=blablabla option)

the compiler error occurs, If I do not include this declaration, every
think is OK ... (or if the xmlns declaration include ";assembly=",
every thing is OK too)

could you help me ?

My computer work fine a few days ago, I don't why I have this error
now ....

Thanks a lot for your help

Bests Regards