General FTP error: Transfer failed due to ftp errors. If it isn't clear from the code and comments what caused the error, and it continues to occur, please contact us and we will investigate.
File not found: Usually a result of a hardware error on our end. You can resubmit the request and usually the problem goes away. If it doesn't, please contact us.
File not processed: If you receive this error and cannot subsequently retrieve the data, please let us know.
Dataset does not exit: This can result when you have submitted a request using the customize retrieval options, or have edited your request file. Double check that there are no errors in the filenames, classes and extension you requested. If you are certain that this file should exist, please contact us and we will look into it.