Need help, Launcher Error

So, whenever I try to boot up Garry’s Mod, I get a launcher error saying the following:

"Failed to load the launcher DLL:

%1 is not a valid Win32 Application."

I tried reinstalling Garry’s Mod and restarting my computer, but neither of those things worked. Wat do?

You need an upgrade.

Well, how do I upgrade then?

Your OS. As far as I know, you’re issue resides in either low specs, or running on XP. If you’re running dualboot with Win7 or something, and this still happens, I don’t know what else you can do.

It’s most likely low specs, considering Garry’s Mod has always worked on my Windows XP. How do I deal with low specs?

Upgrade your hardware, and/or verify your Garry’s Mod game cache.

How do I verify my game cache? That’ll probably do it.

In your Steam library, right click Garry’s Mod and open up “Properties.” A pop up window should open. Choose the “Local Files” tab and in that menu hit “VERIFY INTEGRITY OF GAME CACHE…” Let the process finish completely. Also, go into your Garry’s Mod directory and delete your garrysmod/** folder, and ensure you’re unsubscribed to every addon in the workshop via the Steam workshop menu, rather than ingame before you delete your root folder.

**located at:


Computer/(C: Drive)/Program Files (x86)/Steam/steamapps/[YOUR USERNAME]/garrysmod/ <-- DELETE THIS ONE

If this doesn’t rectify the problem, a recent engine change could have fucked you over due to your OS and system specs, so I would recommend a much needed upgrade to Win8 or Win7 if you’re afraid of change.