I am receiving an 550 error when attempting upload to an FTP site via PutFile

Question

Hi

This FTP site has been relocated to a new IP, however it is resolving to the new address fine. There may have been other firewall related changes also. I can connect to the new site fine, however when attempting to upload the file, I receive a:

The specified network name is no longer available (550).

I can upload via other programs e.g. Filezilla fine, however when in IIS context it consistently gets this error when attempting the upload.

Below is the full log of the request.
Please let me know if you need any other info.

2019-08-18 09:35:51.756 Opening log file.
2019-08-18 09:35:51.759 INFO FileLogWriter(1)[10] Info: Assembly: Rebex.Common 2019 R1 for .NET 4.0-4.7
2019-08-18 09:35:51.761 INFO FileLogWriter(1)[10] Info: Platform: Windows 10.0.17763 32-bit; CLR: 4.0.30319.42000
2019-08-18 09:35:51.775 INFO Ftp(1)[10] Info: Connecting to ftp-syd.dbs.tv:21 using Ftp.
2019-08-18 09:35:51.775 INFO Ftp(1)[10] Info: Assembly: Rebex.Ftp 2019 R1 for .NET 4.0-4.7
2019-08-18 09:35:51.775 INFO Ftp(1)[10] Info: Platform: Windows 10.0.17763 32-bit; CLR: 4.0.30319.42000
2019-08-18 09:35:51.775 INFO Ftp(1)[10] Info: Using proxy HTTP CONNECT proxy:8080.
2019-08-18 09:35:51.805 INFO Ftp(1)[10] Response: 220 Microsoft FTP Service
2019-08-18 09:35:51.811 INFO Ftp(1)[10] Command: AUTH TLS
2019-08-18 09:35:51.814 INFO Ftp(1)[10] Response: 234 AUTH command ok. Expecting TLS Negotiation.
2019-08-18 09:35:51.911 INFO Ftp(1)[10] TLS: State StateChange:Negotiating
2019-08-18 09:35:51.930 INFO Ftp(1)[10] TLS: Negotiating TLS 1.2, RSA with ephemeral Elliptic Curve Diffie-Hellman, AES with 256-bit key in GCM mode, AEAD.
2019-08-18 09:35:52.031 INFO Ftp(1)[10] TLS: State StateChange:Secured
2019-08-18 09:35:52.031 INFO Ftp(1)[10] TLS: Connection secured using cipher: TLS 1.2, RSA with ephemeral Elliptic Curve Diffie-Hellman, AES with 256-bit key in GCM mode, AEAD.
2019-08-18 09:35:52.034 INFO Ftp(1)[10] Command: USER ftp-syd.dbs.tv|tvsn99
2019-08-18 09:35:52.039 INFO Ftp(1)[10] Response: 331 Password required
2019-08-18 09:35:52.039 INFO Ftp(1)[10] Command: PASS **********
2019-08-18 09:35:52.043 INFO Ftp(1)[10] Response: 230 User logged in.
2019-08-18 09:35:52.044 INFO Ftp(1)[10] Command: FEAT
2019-08-18 09:35:52.049 INFO Ftp(1)[10] Response: 211-Extended features supported:
2019-08-18 09:35:52.049 INFO Ftp(1)[10] Response: LANG EN*
2019-08-18 09:35:52.049 INFO Ftp(1)[10] Response: UTF8
2019-08-18 09:35:52.049 INFO Ftp(1)[10] Response: AUTH TLS;TLS-C;SSL;TLS-P;
2019-08-18 09:35:52.049 INFO Ftp(1)[10] Response: PBSZ
2019-08-18 09:35:52.049 INFO Ftp(1)[10] Response: PROT C;P;
2019-08-18 09:35:52.049 INFO Ftp(1)[10] Response: CCC
2019-08-18 09:35:52.049 INFO Ftp(1)[10] Response: HOST
2019-08-18 09:35:52.049 INFO Ftp(1)[10] Response: SIZE
2019-08-18 09:35:52.049 INFO Ftp(1)[10] Response: MDTM
2019-08-18 09:35:52.049 INFO Ftp(1)[10] Response: REST STREAM
2019-08-18 09:35:52.049 INFO Ftp(1)[10] Response: 211 END
2019-08-18 09:35:52.051 INFO Ftp(1)[10] Command: OPTS UTF8 ON
2019-08-18 09:35:52.054 INFO Ftp(1)[10] Response: 200 OPTS UTF8 command successful - UTF8 encoding now ON.
2019-08-18 09:35:52.057 INFO Ftp(1)[10] Command: NOOP
2019-08-18 09:35:52.061 INFO Ftp(1)[10] Response: 200 NOOP command successful.
2019-08-18 09:35:52.063 INFO Ftp(1)[10] Command: CWD ToDeluxe/Schedules/TVSNNZ
2019-08-18 09:35:52.067 INFO Ftp(1)[10] Response: 250 CWD command successful.
2019-08-18 09:35:52.080 INFO Ftp(1)[10] Command: PBSZ 0
2019-08-18 09:35:52.084 INFO Ftp(1)[10] Response: 200 PBSZ command successful.
2019-08-18 09:35:52.084 INFO Ftp(1)[10] Command: PROT P
2019-08-18 09:35:52.088 INFO Ftp(1)[10] Response: 200 PROT command successful.
2019-08-18 09:35:52.089 INFO Ftp(1)[10] Command: TYPE I
2019-08-18 09:35:52.093 INFO Ftp(1)[10] Response: 200 Type set to I.
2019-08-18 09:35:52.095 INFO Ftp(1)[10] Command: PASV
2019-08-18 09:35:52.099 INFO Ftp(1)[10] Response: 227 Entering Passive Mode (185,29,229,164,156,93).
2019-08-18 09:35:52.108 INFO Ftp(1)[10] Command: STOR 20190818_004.xml
2019-08-18 09:35:52.114 INFO Ftp(1)[10] Response: 125 Data connection already open; Transfer starting.
2019-08-18 09:35:52.116 INFO Ftp(1)[10] TLS: Data connection: State StateChange:Negotiating
2019-08-18 09:35:52.128 INFO Ftp(1)[10] TLS: Data connection: Alert Alert:Alert was sent.
2019-08-18 09:35:52.128 INFO Ftp(1)[10] TLS: Data connection: State StateChange:Closed
2019-08-18 09:35:52.133 INFO Ftp(1)[10] Response: 550 The specified network name is no longer available.
2019-08-18 09:35:52.140 ERROR Ftp(1)[10] Info: Rebex.Net.FtpException: The specified network name is no longer available (550).
at Rebex.Net.Ftp.hdvt(String dm, Boolean dn, fmob dp, rtup dq, Int64 dr, FtpTransferState ds)
at Rebex.Net.Ftp.hdxt(String hc, String hd, Stream he, Int64 hf, Int64 hg, rtup hh)
2019-08-18 09:37:08.605 INFO Ftp(1)[10] Command: QUIT
2019-08-18 09:37:08.609 INFO Ftp(1)[10] Response: 221 Goodbye.
2019-08-18 09:37:08.609 INFO Ftp(1)[10] TLS: Alert Alert:Alert was sent.
2019-08-18 09:37:08.609 INFO Ftp(1)[10] TLS: State StateChange:Closed

Answer 1

The 550 The specified network name is no longer available. is server side error. The client cannot do nothing about that.

The error is very probably not related to FTP protocol at all.

It seems like the server tried to store the file on a network shared drive, it got the above error from Windows and it simply respond to the FTP client with the error.

If FileZilla is working, you are doing probably something slightly different. E.g:

• You are not uploading to ToDeluxe/Schedules/TVSNNZ directory.
• You are not using HTTP PROXY.
• You are not using secured data transfers.
• You are not using the same device or network.

Is something from the list above true?

Comments

Hi Lukas

You are right - I don't require the proxy details when sending via Filezilla.  However I did from my code, within IIS.  I spoke to networks and they advised me the proxy is very old, and that they can allow me to send files bypassing the proxy - which immediately worked.

So my best guess is that perhaps security was improved on the new FTP server (TLS perhaps) versus their old server, which was incompatible with the proxy.  It was interesting that it let me connect though, but it was when I attempted to uploaded that things went pear shaped.

Thanks for your help with this - this issue is now resolved.