# .NET and More > Silverlight >  [RESOLVED] dll error

## arkiboys

Hi,
I am running visual studio 2010 premium with silverlight toolkit 4.
The project does not build and in references, the following dlls have yellow exclamation next to them:
1- Microsoft.Expression.Interactions
2- System.Windows.Interactivity

How can I solve these please?
Thanks

----------


## RobDog888

Did you copy/paste the code in from some example or web post?
Sounds like you are missing a reference or two.

----------


## arkiboys

yes. corrected the path to the dlls.
Solved.
Thanks

----------

