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Fix Null Reference Exception in Unity

Here I have another debugging tutorial on how to fix a NullReferenceException error in Unity. This lesson will teach you more about receiving a Null Reference Exception error. I will teach you when and how one might receive this kind of error and then I will teach you how to fix this error so you are no longer receiving a null reference exception error.

In this example, I am receiving a NullReferenceException because whenever I left click with my mouse I send out a raycast from the camera to the mouse position in world space. If there is no object for my raycast to hit then it will return a null value and save it into a variable. I then try to get the tag of that variable but because the object is null it throws the Null Reference Exception. You can fix this error by first checking to see if the return hit value is null. If it is null then you will want to do nothing but if it returns a proper value then you can access the tag.

Now you don’t always want to just check to see if the value is null. Depending on the circumstance the value of what you are accessing might be required for the logic of your game. In this case, yes, you might not be receiving the NullReferenceException error anymore but your game will also not work properly.

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Can’t Switch Build Platforms – Your License does not Cover

In this video, we cover a problem that I was running into just the other day. This problem deals with not being able to switch over to a different build platform like iOS or Android. This problem can be a bit tricky as Unity does not give you very much information about the problem. To fix this problem you will need to re-register your Unity license, even if you are just using the free personal license. Then once you restart it should be all working again.

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Fix Error IL2CPP.exe Did Not Run Properly

You may come across this error if you are ever trying to create an Android build for the Google Play store. This error occurs if you are trying to make a 64-bit architecture build of your game and you are using the wrong version of the Android NDK. This error is also more common because Google will now be requiring your APK in both 32 and 64-bit. This will require you to switch the scripting backend from Mono to IL2CPP and then you have to select the different architecture you want to build for and this is when this error occurs but this error only occurs when you try to build your project. To fix this error you need to download an older version of the Android NDK. The version you need is Android NDK r16b and here is the link to download it. You then have to set the address of you NDK in the External tools of Unity. After doing this The errors should be gone and you should now be able to create a 64-bit APK of your game in Unity.

Documentation:
https://forum.unity.com/threads/googleplay-64bit-console-warning.672988/
https://forum.unity.com/threads/2019-1-10f1-wont-build-to-android-device.709610/

NDK: https://developer.android.com/ndk/downloads/older_releases.html