Can't Launch Undertale

Can't Launch Undertale Game On Steam. How To Fix It?

You might have encountered a problem whereby you cannot launch a game called Undertale. This is an 'indie' video game about a child who must help to return from underground to the surface of the Earth - this is the main quest of the game, during which the player must combat various monsters and avoid attacks. Undertale is a role-playing game in which you can change the story-line by making different choices, thus making it more interesting.

During the game, players are required to complete various tasks and fight monsters to make progress in the story. For example, solving various puzzles or avoiding attacks. You can play this game on Microsoft Windows, OS X, Linux, PlayStation 4, and PlayStation Vita, however, some Microsoft Windows users have reported that they were unable to launch Undertale on Windows computers. Unfortunately, this is not one of the game's quests, but is indeed a problem that needs to be addressed if you want to begin solving more interesting puzzles within the game itself! To resolve this problem, you might need to repair local files using Steam tools, launch the game from its location in the operating system, delete the steam_api.dll file, extract the Undertale.exe file, or reinstall the game itself. In this guide, a number of methods are outlined to resolve the problem so that you can launch Undertale without any problems.

cant launch Undertale

Table of Contents:

Verify Integrity Of Game Files

In this method, we demonstrate how to repair local files (verify the integrity of game files). This process compares game files installed on the computer with the latest versions on Steam servers. If the game files are different, it replaces them or adds additional files necessary for games to run properly. To verify game files' integrity, restart the computer and then launch Steam. Go to the Library section, right-click the Undertale game, and select "Properties" from the contextual menu.

verify integrity of game files step 1

Go to the "LOCAL FILES" tab and click "VERIFY INTEGRITY OF GAME FILES". Steam will start verifying game files. Once the process is complete, files will be re-downloaded and replaced by Steam. This process can take several minutes. Restart the Windows operating system and try to launch Undertale on Steam to see if the problem persists.

verify integrity of game files step 2

[Back to Table of Contents]

Launch Game Using Its Executable File

If the problem is not with the game itself but with the Steam client, you might be able to launch the game using its executable file. In this method, we demonstrate how to easily find the installation folder and launch the game from there. First, open the Steam client and go to the Library section. Right-click the Undertale game and select "Properties" from the contextual menu.

launch game using its executable file step 1

Go to "LOCAL FILES" tab and click the "BROWSE LOCAL FILES..." button.

launch game using its executable file step 2

You will be directed to the Undertale game installation folder. Double click the folder and find the Undertale executable file, which should have the ".exe" extension. Check if you are able to launch the game in this way.

launch game using its executable file step 3

[Back to Table of Contents]

Temporary Disable Your Antivirus

It is possible that installed antivirus software is interfering with the Steam client or the Undertale game itself. To make sure that installed third-party antivirus software is not the problem, temporarily disable it. Try to re-launch Undertale and check if the problem persists. If disabling (or uninstalling) your antivirus software helps, we recommend that you to switch to another product or reinstall the currently version. If you are not sure how to disable your antivirus software, read this guide where you will find instructions on how to disable some of the most popular antivirus programs.

[Back to Table of Contents]

Extract Undertale.exe

We found a solution online that has worked for some users and, therefore, might be an option for you. This method requires extracting the Undertale.exe application using the WinRAR (or another archive utility). Launch the Steam client and right-click the Undertale game whilst in the Library and select "Properties".

extract undertale.exe step 1

Go to "LOCAL FILES" tab and click the "BROWSE LOCAL FILES..." button.

extract undertale.exe step 2

You will be directed to the Undertale game installation folder. Double click the folder and find the Undertale executable file - right-click it and select the "Extract Here" option.

extract undertale.exe step 3

You will be asked if you would like to replace the existing file with the new one. Click the "Rename" option.

extract undertale.exe step 4

Rename the file by giving it a Undertale2 name (or whichever name you prefer) and click "OK". A new game launcher will be extracted - use it to launch the game and check if you are now able to launch Undertale without any problems.

extract undertale.exe step 5

[Back to Table of Contents]

Delete Steam_api.dll

Another way to resolve this problem is to delete the steam_api.dll file - some users have reported that this simple fix worked and they were able to launch Undertale. To delete the steam_api.dll file, go to the Undertale installation folder and find the steam_api.dll file. This is used to launch games through the Steam client. Right-click it and select the "Delete" option from the contextual menu.

delete steam_api.dll

Now try to launch the game using both methods: using the executable file (Undertale.exe) in the game installation folder, and; using the Steam client. Technically, the second option should not work, but some users claimed that this method was successful.

[Back to Table of Contents]

Reinstall Undertale

Finally, reinstall Undertale. Go to the Steam client, find the Undertale game in the LIBRARY and right-click it. Select the "Uninstall..." option from the contextual menu. Wait for the uninstallation process to complete, find the game in Steam, and reinstall it. Check if this solves the problem.

reinstall undertale

We hope that one of the above methods solved the problem and you are now able to launch Undertale using the Steam client or the Undertale.exe file. If you know of other solutions to this problem, not mentioned in our guide, please share them with us by leaving a comment in the section below.

[Back to Table of Contents]

[Back to Top]

About the author:

Tomas Meskauskas

I am passionate about computer security and technology. I have an experience of 10 years working in various companies related to computer technical issue solving and Internet security. I have been working as an editor for pcrisk.com since 2010. Follow me on Twitter to stay informed about the latest tech news or online security threats. Contact Tomas Meskauskas.

Our guides are free. However, if you want to support us you can send us a donation.