4. Delete the Steam_api.dll file
- Close your Steam and kill all its related processes in Task Manager.
- Go to the Undertale installation folder.
- Find the steam_api.dll file and back it up.
- Delete the files from the folder.
- Start the game using Undertale.exe.
- Additionally, you may try and run it through Steam if Undertale.exe won’t start the game.
Note: This may prove harder to do for many games, but the Undertale should function well. If things take a wrong turn, you can always restore a file from the backup location.
It’s quite hard to play Steam games independently, without Steam DRM. However, there are some games that are DRM-free, and luckily, that is the case with Undertale, too.
5. Install DirectX and the latest redistributables
Also, an important thing, besides your graphics drivers being up to date, is to install the latest version of DirectX and C++ Redistributables.
The absence of those might lead to you experiencing a plethora of issues with Undertale.
The latest version of DirectX can be downloaded from the dedicated Microsoft website.
When it comes to the Visual C++ Redistributables, you can download the latest version from this Microsoft page.
6. Reinstall the game
- Go to the Steam client.
- Open Library and right-click Undertale.
- Choose Uninstall.
- Open the Steam client and Library.
- Find Undertale and select Install.
We came to the last resort. If you haven’t solved your Undertale issues with the previous workarounds, reinstallation is the only viable option.
After the process is finished, you should be able to play the game seamlessly.
We hope you were able to start the game by using these workarounds. In addition, if you have any questions or suggestions, please be free to tell us in the comments below.
Editor’s Note: This post was originally published in April 2019 and has been since revamped and updated in October 2020 for freshness, accuracy, and comprehensiveness.