I’ve previously used TestComplete to automate our Windows desktop apps (VB6 and WPF), but since the license wasn’t renewed and support has lapsed, I’m now looking for a free or open-source alternative to maintain a basic regression suite.
Ideally:
If you’ve worked with any reliable tools under similar constraints, I’d genuinely appreciate your suggestions. Thanks in advance! 
I’ve been working in desktop automation for a few years now, mostly around .NET and WPF apps, and I’ve had a really solid experience with one tool in particular.
FlaUI is a Modern C# Framework for Windows UI Automation If you’re looking for free/Open Source Tools to Automate Desktop Apps (VB6, .NET, WPF), FlaUI is definitely worth trying. It’s a modern C# library that wraps the UI Automation APIs nicely and gives you a lot of control.
There’s no record-playback here, but if you’re comfortable coding in C#, it’s a powerful option. I switched to FlaUI after dropping a paid tool and haven’t looked back — especially great for regression tests using NUnit or MSTest.
One huge plus: it works on Windows 7 too, as long as you’ve got .NET 4.6 or higher. So even for older systems, FlaUI holds up really well.
There’s something called White Framework which is stable for legacy apps and Windows 7.
In a previous role, we had to maintain regression tests for a legacy VB6 system running on Windows 7, and White Framework helped us bridge the gap. It’s an open-source automation library for Windows desktop apps, built on Microsoft UIAutomation.
White is older than FlaUI but still functional for classic Win32 and .NET apps. It offers a simple abstraction for windows, controls, and user actions — great for scripting in C# without needing advanced config or modern dependencies.
While it might not be actively maintained, it performs well in stable test environments where you need consistency over flashiness. If your app’s UI elements don’t change too frequently, White could be a reliable, lightweight option.
I see @emma-crepeau and @akanshasrivastava.1121 have already answered — and yes, they’re correct — but I know one other tool as well.
It’s called WinAppDriver, a free option from Microsoft that’s ideal with Appium UI. It’s essentially a WebDriver implementation for Windows desktop apps and works really well with .NET-based and WPF apps.
It supports Appium, so if you’re familiar with Selenium/Appium-style scripting, you’ll feel right at home. You can write tests in C# using Appium bindings, and it integrates smoothly with CI/CD tools too.
The catch: WinAppDriver needs a bit of setup and runs better on Windows 10+, though I’ve managed to get it working on Windows 7 with a few workarounds. If you plan to move off Windows 7 down the line, this is a future-proof option you can comfortably start with today.