I downloaded the SQL Developer version
sqldeveloper-4.1.5.21.78-x64
for Windows 7 and tried to open .sql files. I have edited the 'Preferences' for 'File types' to open .sql files. But still, the when clicking .sql file from Windows explorer, or using 'Open with' --> 'sqldeveloper.exe' nothing happens. I also tried the newest version
sqldeveloper-4.2.0.16.356.1154-x64
but it has the same bug. What is the reason for this and how to fix it?