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A client of mine wants to use an FTP Server app called CrushFTP (www.crushftp.com). It looks like a great program. (Simple GUI, powerful features, etc). It has a big problem, though: It is a java based app. When you start it up, it assumes you want to use port 21 for FTP. (the norm). However, you immediately get an error that 'cannot use port 21...' The author of this app offers the following solution (see text between **** below) (Please note that the instructions below are specific to Mac OS X, but I have the same problem in linux) My question: Since I don't want to log on as root, how do I go about giving a user the necessary 'root' privileges? Thanks, Eric Carbone *************** Open a terminal session. To enable CrushFTP to run properly, issue the following command. sudo chmod u+s /System/Library/Frameworks/JavaVM.framework/Versions/1.3.1/Commands/java PLEASE NOTE!!!!!!!!!!!!!!!!!! The reason why this is necessary is because ports below 1025 (such as "21" that an FTP server runs on) are considered reserved ports. Why? Legacy. So, in order to open a server on port 21 you must have permissions. Either log into the computer as root (not recommended), or run the server as if you were the root user (many servers implement this one way or another.) The command you pasted will allow CrushFTP root access to your computer. It will also allow any other .jar file you double click on root access. You have been warned! That said...it works very nice like this. It works like MacOS 9, Windows, even Linux. It's the Unix backbone that makes this necessary. ***************