Invalid AS/400 Command Response Received from AS/400 FTP Server: Error occurred on command WINSPOOL/WSPL020 FILE(XXXX) JOB(####/XXXX/XXXX) SPLNBR(#).
This problem can be caused by a number of issues:
The user may not have *SPLCTL authority set on their AS/400 user profile. If they do not have *SPLCTL authority they can only download reports which were created by their user ID or from an output queue that was created with the DSPDTA(*YES) parameter on the CRTOUTQ command.
The spool file being downloaded was an AFP/IPDS report or had special fonts that won't allow the report to be copied with the CPYSPLF command.
The spool file being downloaded no longer exists in the output queue. Have user refresh spool file list.
If converting AFP report to PDF with the WinSpool/400 Email Report Server the following criteria must be met:
In File / Settings on the AFP/IPDS Tab only the "Enable Native AFP to PDF Converter" needs to be enabled
In Table Entry / Edit Output Queue/Email Recipient List at the Output Queue level the "Output Format" must be set to NAP
If none of the above solutions work, try running the CPYSPLF command on the AS/400 with the report they are having the issue with. The report they are trying to convert might have DBCS data in the report. Look at the KB article in regards to "Converting CCSID Correctly when Downloading Reports"
The spool file may contain Double Byte Characters. Try enabling double byte support using the command: CHGDTAARA DTAARA(WSPLDBCS) VALUE(*YES)