You can Copy a shortcut to EOC (from desktop, etc.) and Paste it into your Send To folder (Google for where this system folder is, if not sure - it varies between different versions of Windows).
Now when you select a file, you can use right-click > Send To > EncryptOnClick and it will run EOC and pass the file name to it, then prompt you for password, then go ahead and encrypt it. This also works for multiple selected files: if you pass N multiple files, then - after processing file #1 - it will prompt for Yes/No/All whether to continue processing files 2 to N
You can also use the Send To entry to decrypt *.EOC files.
Now when you select a file, you can use right-click > Send To > EncryptOnClick and it will run EOC and pass the file name to it, then prompt you for password, then go ahead and encrypt it. This also works for multiple selected files: if you pass N multiple files, then - after processing file #1 - it will prompt for Yes/No/All whether to continue processing files 2 to N
You can also use the Send To entry to decrypt *.EOC files.