Switch -ME[par] - set encryption parameters
Use -mezl switch together with -p[pwd] to create an encrypted ZIP archive using ZIP legacy encryption algorithm. Without -mezl ZIP archives are encrypted with AES-256, which is more secure, but can be incompatible with some older versions of unzip tools.
Use -mes switch to skip encrypted files when extracting or testing.
create an encrypted archive with ZIP legacy encryption
WinRAR a -s -pmypassword -mezl docs.zip *.txt