why am i recieving this error its the first time for me. all ive done recently is build my levels lighting and after that i couldnt save the item in the msgs and this msgs continues to appear.
I’ve had this problem also.
For me I somehow manage to open the same project twice and had them running at the same time, but only working in one of them. When I tried to save the same error appear because the other project was also using the same map.