Error 15550 When Transmitting Files Using FTP

Updated Dec 18, 2023

Reported In


  • LabVIEW



Issue Details

I'm using FTP to transmit files but I got the error 15550 when using FTP Put as follows:
Error 15550 occurred at FTP Transaction: 550 The parameter is incorrect.


The Remote Write Path of FTP Put should be the file path instead of directory path on the FTP server.  This is the same for the Remote Path of FTP Get

Additional Information

Sometimes you may get a similar error saying:
Error 15550: FTP Transaction: 550 Could not open file.

If you are trying to move files from the system folder to an external drive, then this error could come up if the filepath is incorrect or if the external hard drive is no longer seen by the machine. Troubleshooting steps in this case could be checking the external hard drive on another machine to see if you can use it, trying a different external hard drive if it has never worked, and also making sure that the filepath does exist.

If you are using FTP VIs to move files,  the creation of a new folder on the RT target from the host PC does not automatically occur.  There is a VI in the FTP VI library that provides this functionality.  This VI is not located on the FTP palette and must be browsed to at this location:

labview\vi.lib\addons\internet\ftp\ftp1.llb\FTP [MKD].vi

You can simply use this VI to create a new folder, then use the FTP Put to store files in that new folder.