Tip for the day: If you get the error "Type provider assembly ... is not trusted..."

Tip for the day: If you get the error ""Type provider assembly ... is not trusted and will not be loaded for security reasons" and you want to explicitly opt-in to trusting it, then

  1. Go to the Tools --> Options --> F# Tools --> Type Providers" in Visual Studio
  2. Tick the assembly.or add a new entry for it

The error will appear if

  • You said "no" to trusting the assembly when the choice was first offered to you (e.g. maybe you pressed return or space quickly without noticing when the dialog appeared)
  • You used a type provider from F# Interactive without first using it from a script or project in Visual Studio

The Visual F# team