Activities cannot find .NET Runtime

Observed Behavior

Workflows using specific activity packages fail when run on 2023.4.0 and newer robots with one of the following errors:

• "To run this application, you must install missing frameworks for .NET."
• "To run this application, you must install .NET."

The following activity packages are impacted:

• UiPath.Form.Activities version 2.0.x
• UiPath.IntelligentOCR.Activities
• UiPath.MobileAutomation.Activities
• UiPath.Vision
• UiPath.DocumentUnderstanding.Activities
• OCR related activities in the UiPath.UIAutomation.Activities package
• UiPath.OmniPage.Activities
• UiPath.OCR.activities

Resolution A

Upgrade the activity packages of the affected workflows to the following versions:

• UiPath.Form.Activities 2.0.x -> 2.0.7
• UiPath.IntelligentOCR.Activities -> 6.9.1
• UiPath.MobileAutomation.Activities -> 23.4.0
• UiPath.Vision -> 3.10.1
• UiPath.DocumentUnderstanding.Activities ->2.2.2
• OCR related usage from UiPath.UIAutomation.Activities fixed in ->23.4.5
• UiPath.OmniPage.Activities -> 1.15.0
• UiPath.OCR.activities -> 3.15.1

Resolution B

Add an Invoke Code activity at the start of the affected workflow with the following statement: “System.Environment.SetEnvironmentVariable("DOTNET_ROOT", System.AppContext.BaseDirectory)”.

Resolution C

Install .NET Windows runtime or missing frameworks for .NET on the machine.