Invalid editor window UnityEditor.FallbackEditorWindow UnityEditor.EditorApplicationLayout:SetPlaymodeLayout()

Hello, I’ve got a really big problem in Unity, with each new project, event if it’s empty, when I’m tryin to start the game, the game is breaking and I’m getting the same Error as it is in the title :(.
Can someone help me fixing it?
I have reinstalled the Unity, but it doesn’t help.

Figured it out!

Did a quick google search and found the right link this time.

Go to Window > Layouts > Revert To Factory Settings.
(It will erase any layouts you currently have). Tested and works for me now.

Best answer is cool, but you not need to reset all settings, for me it was solved just by changing layout and returning back to my own.

i was having a Similar problem and the solution seemed to be that i didnt have my layout set to anything. If you see [Layout] at the top right of your screen then thats probably why and u need to either set it to what ever custom layout youve made or a defualt layout but it shouldnt say layout regardless. if this doesnt work then you can reset to default but thats last resort because then you delete your custom layouts.
@N1warhead

I didn’t want to delete the layers and found another solution. It worked for me by closing the scene window (just right click the scene tab and click on close tab) and then reopen it again with

Window > General > Scene.

The other solutions commented here didn’t work for me. Maybe this is the solution for you.

This is another really STUPID error, and shouldn’t even exist. Unity seems to want you to pick an existing saved layout - either a factory preset, or one you’ve saved - and then never change it without updating the saved layout. The only problem is that during normal use, Unity will often forget which layout you’re using. Maybe you accidentally moved a window border, or some other minor detail about the layout changes - then next time you start Unity, the selected layout will be blank, and you start getting errors. Totally unnecessary to even check for this, let alone pester users all the time with annoying errors about NOTHING.

Ya I get them all the time too. Makes me REthink my opinion on how ‘great’ unity is. I don’t get to , on top of weird stupid as you say, choice of window layout choice, a 3rd person char bc apparently Unity doesn’t think enough of us are too poor not to get one in store so they make even more money. Lastly I can’t even have WATER,unlike ue4 which gives it to us out of the box, bct that too requires extra out of pocket purchases, unless I’ve missed something? ( hoping)

So ya…

For me, it was the shader graph window that I had open, once I closed that, the error went away…

Turn maximize play off on the game window. Seems to trigger this error when I dock the game window.

The Solution is ,
Windows> layout> Default

i know it’s an old post, but u can fix it without resetting your layout completely, save your layout, change to default layout and then back to your saved layout

problem fixed here : Invalid editor window Unity - YouTube

I solve this problem in a similar way as @iTzWayne without reseting or changing layout nor closing any window.

The problem appears for me when I select “Maximize on play” for the GameWindow. I don’t why this cause the error because it worked before for me.

Work for me this solution!
Thank you.

This is easily fixed by reloading a saved layout, but it persistently returns, doesn’t it? I think this likes to happen when we have the ProBuilder preview package docked in our Editor.

Try turning off Maximize on Play. It sends the error as well.