Wing FTP Software

we are sychronize Directorys with FTP Voyager to WingFTP

since 7.12.19 ftp Voyager give the order to Change to passive mode but Wing FPT Server said only 500 unknown command

HOST xy
[04] Fri, 08 Dec 2017 10:59:42 (0000026) 500 Unknown command.
[03] Fri, 08 Dec 2017 10:59:42 (0000026) USER ipad
[04] Fri, 08 Dec 2017 10:59:42 (0000026) 331 Password required for ipad
[02] Fri, 08 Dec 2017 10:59:42 (0000021) Closed session, disconnected from 10.93.12.37
[03] Fri, 08 Dec 2017 10:59:42 (0000026) PASS **********
[04] Fri, 08 Dec 2017 10:59:42 (0000026) 230 User ipad logged in.
[03] Fri, 08 Dec 2017 10:59:42 (0000026) SYST
[04] Fri, 08 Dec 2017 10:59:42 (0000026) 215 UNIX Type: L8
[03] Fri, 08 Dec 2017 10:59:42 (0000026) FEAT
[04] Fri, 08 Dec 2017 10:59:42 (0000026) FEAT response message.
[03] Fri, 08 Dec 2017 10:59:42 (0000026) REST 100
[04] Fri, 08 Dec 2017 10:59:42 (0000026) 350 REST supported. Ready to resume at byte offset 100.
[03] Fri, 08 Dec 2017 10:59:42 (0000026) REST 0
[04] Fri, 08 Dec 2017 10:59:42 (0000026) 350 REST supported. Ready to resume at byte offset 0.
[03] Fri, 08 Dec 2017 10:59:42 (0000026) CLNT FTP Voyager 16.2.0.328
[04] Fri, 08 Dec 2017 10:59:42 (0000026) 200 Noted.
[03] Fri, 08 Dec 2017 10:59:42 (0000026) OPTS UTF8 ON
[04] Fri, 08 Dec 2017 10:59:42 (0000026) 200 OPTS UTF8 ON
[03] Fri, 08 Dec 2017 10:59:42 (0000026) PWD
[04] Fri, 08 Dec 2017 10:59:42 (0000026) 257 "/" is current directory.
[03] Fri, 08 Dec 2017 10:59:42 (0000026) MLST /
[04] Fri, 08 Dec 2017 10:59:42 (0000026) 250-Listing Begin
type=dir;perm=drwxrwxrwx;modify=20171208091408; /
250 End.
[03] Fri, 08 Dec 2017 10:59:44 (0000023) QUIT
[04] Fri, 08 Dec 2017 10:59:44 (0000023) 221 Goodbye.
[02] Fri, 08 Dec 2017 10:59:44 (0000023) Closed session,disconnected from xy
[03] Fri, 08 Dec 2017 10:59:45 (0000024) QUIT
[04] Fri, 08 Dec 2017 10:59:45 (0000024) 221 Goodbye.

Yes, FTP command "HOST xxx" is an unknown command for WingFTP, but from your server logs, it seems such command won't effect FTP access.