@deleted-user-s_pSF_cCqVzk ,
By default, tools are run “in the background” meaning that while a tool is running you can do other stuff with ArcMap. When a conflict arises, the part of the code that does this (the background server) throws an exception (the actual technical term is “throws a wobbly”). You can fix this by going to the Geoprocessing Menu and looking for “Geoprocessing Options”. In the window that pops up, untick the Enable Background Geoprocessing:

The downside of this is that you won’t be able to do other work until the tool has finished its work.
http://blogs.lincoln.ac.nz/gis/2019/02/21/fixing-common-arcgis-problems/
I hope that helps.