I/O problem, file not completed (451)

Question

Hi Rebex Team,

We have integrated Rebex FTP/SFTP components in our .NET WPF application. The components are working fine for all types of FTPs. But recently we got an error "Requested action aborted: I/O problem, file not completed (451)." from one of our FTPs while downloading the file (client.GetFile) method. We have retried multiple times and had the same issue.

But we don't have this issue while we are downloading the files from FileZilla.

Ftp client = new Ftp();
client.Connect(ftpSettings.ServerName, ftpSettings.PortNumber);
client.Login(ftpSettings.UserName, ftpSettings.Password);
client.GetFile(ftpPath, destinationPath);

The FTP Hostname is na1p50.ftp.b2b.ibmcloud.com

This is a production issue and it is very critical for us to fix it asap. Please help us to resolve this error.

Thanks & Regards
Krishna Kishore
AIMS360

Answer 1

Please note that FileZilla has a habit of silently resuming failed transfers, so first please make sure it's not doing that without your knowledge (should be apparent from its log).

If not, create a debug log using https://www.rebex.net/kb/logging/ and either post it here or mail it to us for analysis. This will make it possible to tell where and when exactly the error occurred. Also, post a FileZilla log as well to make it possible to determine whether it's doing anything differently. Thanks!