Running IPSwitch WS_FTP on Windows Server 2003 SP1 - Data Execution Prevention (DEP)
I had a problem running WS_FTP (http://www.ipswitch.com/products/ws_ftp/index.asp) on my Windows Server 2003 machine with SP1. Whenever I would start an FTP transfer the application would crash. Finally I figured out it was Data Execution Prevention that was preventing it from running. Data Exection Prevention monitors your programs to determine if they use system memory safely. To do this, DEP software works alone or with compatible microprocessors to mark some memory locations as "non-executable." If a program tries to run code—malicious or not—from a protected location, DEP closes the program and notifies you. [REFERENCE: WINDOWS HELP]
DEP can be found under System Properties > Advanced Tab > Performance Settings > Data Execution Prevention Tab
Allowing WS_FTP in the above dialog solved the problem.