Resolution:
Problem description:
1) Can login to FTP server with other FTP tool or command line
2) Can not connect to the FTP server using "FTP connection" from designer
3) Error message "Invalid User name or Password"

We have seen several such cases caused by the same reason, which is at the FTP Server side, the FTP banner string contains the "line feed" character. For example, when using TCPTrace tool to trace the data between FTP client and server, it may have following trace:
-----------
220-WELCOME to RMS
220-
220 Secure FTP Server
ready.
331 Password required for netwappl.
------------

We can see before line 331, there is a "new line" for words "ready", which causes the confusion in BW side. After removing the new line, the problem gets fixed.