Due to the confusion arised from us, I would like to clarify the following points :

1. Winzip can accept command line manipulation through FoxPro.
2. Winzip can be done "undetected".
3. Personally, I don't have Dynazip.
4. At last, I have been using Winzip for years...

Several things we must consider, What do you want Winzip to do? just zipping and unzipping a directory or files. Or you are going to create a backup in the floppy disk?

One thing is that when you try to run a program from VFP, if the time span on the program you run is too long, the VFP will go to next line, "neglect" the program. and rush ... rush...

In this case, the zip file we want to create is not yet available for use, but the next line will try to upload to the server, and create the ERROR. In the file section, there is a program called API_APPRUN solve this problem very well.

Winzip is so easy to use,
WINZIP.EXE -min -a -r -p -ex DATA.ZIP c:\data\*.*

This will add all file in c:\data\ to DATA.ZIP with minimal window.

And there is complete note on Winzip site on FAQ section.
"What command line parameters does WinZip support?"

Hopefully, this note will help you all.

e.g.
oProcess = CREATEOBJ('API_AppRun','c:\progra~1\winzip\WINZIP32.EXE -min -e -o -j download.zip c:\health&care\download\','C:\','MIN')

oProcess.LaunchAppAndWait()