Error with workflow and views module

Hello,

I installed the workflow module version 7.x-1.0 with the views module version 7.x-3.x-dev with Drupal 7.10. When I click on the menu summary workflow I get the following error:
Fatal error: Unsupported operand types in C:\wamp\ www\drupal\ sites\all\modules\views\handlers\ views_handler_filter_in_operator.inc on line 158.

Also the type of content workflow does not exist and the following error appears on the screens admin

Notice: Undefined variable: workflows in workflow_views_handler_filter_sid-> get_value_options () (line 21 in
Notice: Undefined variable: states in workflow_views_handler_filter_sid-> get_value_options () (line 34 in

Has anyone ever encountered this error and if so what is the solution?

Thank you