I did everything I could, but this problem never left me.
Do you have another solution ?
Thanks
this was the only think that worked for me. must have been something wrong with my map. thank you
Hi, I’ve got the same issue, which occurs when I change the name of my level. I changed the ThirdPersonExampleMap name for something else and the editor was crashing when relaunching it. Fix it by going into the project folder config folder and DefaultEngine.ini. and I then modified the name of the level with the same thing that I’ve put in the editor! Hopes this helps!
YOU ARE A GOD !!! THX FOR EXISTY !!!
U just recovered 16h of work (night + early morning).
Thanks a lot, helped for me as well 
Thanks, deleting the config folder alone, worked for me.
This problem started here when in moved the FirstPerson folder into a new folder.
When i edited the DefaultEngine.ini to the right location in my case:
EditorStartupMap=/Game/FirstPerson/Maps/FirstPersonMap.FirstPersonMap
to
EditorStartupMap=/Game/cw_FPS/FirstPerson/Maps/FirstPersonMap.FirstPersonMap
It al worked fine for me again.
Hope this helps for someone.
No amigo de verdad gracias esto me ha ayudado no había encontrado información en español pero estoy muy feliz de poder haberlo solucionado he eliminado la ruta que estaba escrita en la variable de editor startup map y game default map dejándolos como lo has puesto en el comentario, Como dije he dejado en blanco las rutas de editor startup Map y game default map y me ha funcionado en default engine.ini
This seems to still be an issue, I’m on the latest version of the engine.
I tried @shaq_mobile’s fix, and it did work (thank you! Now I don’t have to re-do the last two months of production!). Though, it would be nice if the engine could proactively fix the issue on its own if it encounters this problem, perhaps it could fall back to a newly created empty map, or the first .umap file it can find.
Worked for me as well. Thank you soooo much!
I was getting the error on quitting. Once I opened the project again, I right-clicked on the top-level “Content” folder and Updated the Redirectors and it discovered a bunch of issues of missing links. I deleted all the redirectors and it solved the crashing on quitting.
This was the fix!
I think it is because I changed the default map in project settings, and then changed the name of the map in the same session.
Thanks to you, I solved it. I hope you will be happy for the rest of your life!!!
thx a lot, worked for me