....you will need to rename keycodes to keycodes.txt (Create a geodatabase in SQL Server—Manage geodatabases in SQL Server | Documentation ). I gonna go with this is not by design, as Server doesn't put an extension on the file. Already logged case, but FYI so you're not frustrated for 2 hours (like I was!).
I had to drag and drop the keycodes file from the folder location. I tried this on Postgres and SQL Server and it worked.
I do see what you are saying that it does not recognize the file without the change.
Let us know when you get a BUG for this one...
BUG-000126285: Authorization File's Browse can't refer 'keycode' file or '*.ecp' file in Create Enterprise geodatabase tool.
Thanks for the info, we're now associated with the BUG and will monitor, as well.
