"Couldn't set association for project. Check the file is writeable"

Hi Guys,

I am in big trouble. I have been working on my project and for some reason I cannot open my project anymore, I am getting this weird message “Couldn’t set association for project. Check the file is writeable”. I am new in Unreal engine

I have 2 days looking for the answer but I couldn’t found it. I am using Unreal engine 4.26.

I saw some guys told me to copied the Win64/UnrealversionSelector.exe but I am unable to find this on my computer.

If you have any video tutorial which can help I will be grateful