You try to launch DSX and Windows stops you with a popup: “You must install .NET Desktop Runtime to run this application.” Frustratingly, some people download what looks like the right framework and still get the same error. Here’s what’s actually going on and how to fix it properly.
Why This Happens
DSX relies on Microsoft’s .NET framework to run. If you download the wrong flavor of it, there are several similarly-named options on Microsoft’s own site, or the wrong processor architecture, Windows won’t be able to link things up correctly, even though it looks like you installed something.
Getting the Right .NET Version
The biggest trap is clicking the first “Download .NET” button you see without checking which specific variant it is.
What to look for:
- DSX needs the .NET Desktop Runtime, specifically version 8.0
- Go to Microsoft’s official .NET download page directly, not a third-party mirror or file-sharing site
- On that page, you’ll see several columns, avoid SDK (that’s for developers building software, not running it) and avoid ASP.NET Core Runtime (that’s built for web servers)
- Look specifically for the column labeled .NET Desktop Runtime
- Under Windows, download the x64 version unless you know you’re specifically on an ARM-based Windows device
Cleaning Up Conflicting Installations
If you’ve already installed a few different runtimes trying to clear the error, leftover conflicting versions can sometimes keep causing problems.
Steps:
- Open Windows Settings (Win + I), then go to Apps, then Installed Apps
- Search for “.NET”
- Look for older or duplicate .NET Runtime or .NET SDK entries that don’t match what you actually need
- Uninstall the ones that don’t match, then restart your PC
- Run the correct
windowsdesktop-runtime-x64.exeinstaller as administrator, and let it finish fully before opening DSX again
If You’re Installing DSX Through Steam
Since DSX is distributed through Steam, Steam typically handles installing required dependencies as part of the install process, you shouldn’t normally need to manually hunt down a zip file or unblock an executable the way older, standalone software sometimes requires. If you’re still seeing this .NET error despite installing through Steam, it usually means the .NET Desktop Runtime specifically wasn’t bundled or completed correctly during that process, and manually installing it yourself (using the steps above) resolves it in most cases.
Confirming DSX’s Drivers Are Also Set Up
Once DSX opens without the .NET error, it’s worth double-checking its underlying driver dependencies are properly in place too, since a missing .NET runtime and missing ViGEmBus driver can sometimes get confused for each other if you’re troubleshooting blind.
Steps:
- Launch DSX as administrator
- Go to Settings and look for a controller or driver setup section
- Confirm ViGEmBus shows as installed and up to date
Without ViGEmBus, DSX can open fine (assuming .NET is sorted) but won’t be able to emulate a controller correctly, a different symptom from the .NET error but worth ruling out while you’re already checking prerequisites.
When Nothing Above Fixes It
Still seeing the error after installing the correct runtime: Restart your PC fully rather than just closing and reopening DSX, some .NET installations don’t take effect until Windows has fully restarted.
Error mentions a specific version number you don’t recognize: Read the exact error text carefully, sometimes it specifies a slightly different version (like 6.0 instead of 8.0) than what you assumed, and installing the exact version referenced resolves it faster than guessing.
You’re on a managed work or school computer: Some organizations restrict software installation entirely. If that’s the case, this isn’t something you can fix yourself, you’d need IT department involvement to install the runtime.
If DSX opens cleanly but your controller still isn’t being detected, that’s a separate issue from anything covered here, our Troubleshooting guide and Drivers page cover connection and detection problems specifically. And if you haven’t installed DSX at all yet, you can grab it from our download page, which links directly to its official Steam listing, our homepage has a broader overview if you’re still deciding whether DSX is the right tool for your setup.
Why This Error Feels So Confusing
Part of what makes this particular error frustrating is that Microsoft’s own download page doesn’t make the distinction between SDK, Desktop Runtime, and ASP.NET Core Runtime obvious at a glance, they’re all just labeled “.NET 8.0” with a subtitle that’s easy to skim past if you’re just trying to get an error message to go away quickly. It’s a genuinely common mistake, not a sign you’ve done something wrong technically, the page itself is laid out in a way that makes the wrong choice easy to make by accident.
A Quick Way to Double-Check What You Have Installed
If you’re not sure whether you already have the correct runtime installed before downloading anything new, open a Command Prompt and type dotnet --list-runtimes. This lists every .NET runtime currently installed on your system, including the version number and whether it’s the Desktop, ASP.NET Core, or base runtime. If you see Microsoft.WindowsDesktop.App 8.0.x in that list, you already have what DSX needs, and the error you’re seeing likely points to a different underlying issue, like a corrupted installation, rather than a genuinely missing runtime