August 23, 2012 Leave a comment
If you see an “unexpected error in Silverlight application” error message when trying to create new sub-sites or other items on a SharePoint 2010 you need to check the web page security validation on your web application. Probably it is set to Off.
To change it:
- Go to Central Administration.
- Go to Application Management > Manage Web Applications.
- Select the web application with the issue and click General Settings on the ribbon.
- Change the Web Page Security Validation from Off to On.
- Click OK to close the dialog.
Test the sub-site creation and the Silverlight should work just fine.