Dynamics University looks at IM error: Could not load file or assembly ‘Microsoft.ReportViewer.WinForms’
IM error: Could not load file or assembly ‘Microsoft.ReportViewer.WinForms’ | Dynamics University
Install, Upgrade & AdminDevelopment & Integration
Archived post from 2013. Dynamics GP and the links it points to have changed since; check current documentation before relying on version-specific steps.