An overlay-loading error can stop a game before its window appears. Error 126 indicates a missing module, but the number alone does not prove the Steam overlay file is the only damaged component.
Step-by-step solution
- Exit the game and fully exit Steam, then restart the computer. Launch Steam normally and allow any client update to finish.
- Try another installed game. If only one title fails, start with that game’s files and supported modifications; if several fail, investigate the client or shared runtime.
- In the affected game’s Steam properties, open Installed Files and run Verify integrity of game files. Wait for it to complete before trying again.
- Check for an unsupported injected overlay or modification added just before the problem. Disable that optional component through its own settings, then test.
- Use the publisher’s prerequisite installers if the game still reports missing dependencies. If the failure affects many games, contact Steam Support before reinstalling the client and preserve installed games and saves.
How to check the fix
Start the same game from its library entry. Confirm both normal gameplay and the overlay shortcut work, if that game supports the overlay.
Before you try other fixes
Copying an overlay DLL from another computer can introduce incompatible versions. Avoid downloading standalone replacements.
