Power Automate Desktop Architecture & Key Components

Power Automate Desktop (PAD) is Microsoft’s Robotic Process Automation (RPA) solution within the Microsoft Power Platform. It enables organizations to automate repetitive tasks across Windows desktop applications, web applications, files, folders, and legacy systems, while integrating seamlessly with Power Automate cloud flows.

This article provides a clear, Microsoft-aligned overview of Power Automate Desktop architecture and its key components, using official terminology to help learners, developers, and enterprises understand how PAD works internally.

What Is Power Automate Desktop?

Power Automate Desktop allows users to create desktop flows that automate tasks performed on a Windows machine. These desktop flows can run:

• Attended (triggered by a user)

• Unattended (triggered automatically without user intervention)

Power Automate Desktop works together with:

• Power Automate (cloud flows)

• Power Automate Machine Runtime

• Microsoft Dataverse

• Power Platform environments

Power Automate Desktop – High-Level Architecture

From a Microsoft architecture perspective, Power Automate Desktop consists of the following core layers:

1. Desktop Flow Authoring Layer

2. Desktop Flow Execution Layer

3. Machine Runtime & Infrastructure Layer

4. Power Automate Cloud & Power Platform Services Layer

Desktop Flow Authoring Layer

This layer is responsible for creating and configuring desktop flows.

Enables users to design desktop flows using Microsoft’s low-code authoring experience.

Component	Description
Power Automate Desktop app	Desktop application used to create and manage desktop flows
Desktop Flow	Automation workflow created in Power Automate Desktop
Desktop Recorder	Records actions performed in Windows desktop applications
Web Recorder	Records browser-based automation steps
Actions Library	Collection of built-in actions for UI automation, files, Excel, Outlook, scripting, etc.
Variables	Store and pass data within desktop flows
Variable Data Types	Text, Number, Boolean, Datetime, List, Dictionary, Custom Object
Control Flow Actions	Condition, Switch, Loop, Error handling actions

Desktop Flow Execution Layer

This layer governs how desktop flows are executed. Ensures desktop flows run accurately and consistently on Windows systems.

Components	Description
Desktop Flow Engine	Executes the desktop flow actions step by step
UI Automation	Automates interactions with desktop and web application UI elements
UI Elements	Identified controls such as buttons, text boxes, windows
Selectors	Properties used to uniquely identify UI elements
Image Automation	Used when UI elements are not accessible
Error Handling Actions	Handle runtime errors and exceptions
Retry & Timeout Settings	Controls execution reliability

Machine Runtime & Infrastructure Layer

This layer defines where and how desktop flows run. Provides the execution environment required for attended and unattended automation scenarios.

Components	Description
Power Automate Machine Runtime	Windows service required to run desktop flows
Machine	Registered Windows device or virtual machine
Machine Group	Group of machines used for load balancing and high availability
Attended Run	Desktop flow executed with a signed-in user
Unattended Run	Desktop flow executed without user interaction
Credential Management	Secure handling of credentials
Session Management	Manages locked and unlocked Windows sessions

 Power Automate Cloud & Power Platform Services Layer

This layer enables orchestration, governance, and monitoring. Delivers enterprise-grade governance, monitoring, and integration with the broader Microsoft ecosystem.

Components	Description
Power Automate (Cloud Flows)	Orchestrates and triggers desktop flows
Cloud Flow Trigger	Event that starts the automation
Desktop Flow Action	Cloud flow action that runs a desktop flow
Microsoft Dataverse	Stores run history, logs, and metadata
Power Platform Environment	Logical boundary for apps, flows, and data
Security Roles	Control access to desktop flows and environments
Monitoring & Run History	Execution status, duration, and errors

Summary

Power Automate Desktop is a core RPA capability of Microsoft Power Platform, designed with a clear separation of authoring, execution, runtime, and cloud orchestration layers. By using Microsoft-defined components such as desktop flows, machine runtime, machine groups, and Dataverse, organizations can build secure, scalable, and maintainable automation solutions.

Understanding this architecture is essential for anyone designing enterprise-ready RPA solutions using Microsoft technologies.