Send feedback on this topic to EmurasoftEmFTP Progress window appears, and the following error message may appear periodically.
Thread #1: [FtpCommand] error code: 12003, the server returned extended information : 500 ": command not understood.
In this case, go to the Advanced tab of Properties, and uncheck the Keep Alive check box. Or, you can check the Keep Alive check box, and enter a command like "NOOP" in the Command to Keep Alive text box.
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