System.IO.IOException: Unable to write data

Question

I get the following exception error message with EnterpriseDT .NET when attempting to upload a file to Windows System 7 FTP server

DEBUG [FTPControlSocket] 17 Jan 2014 07:48:18.157 : ---> STOR _SV-NYSE-dyn.qti
DEBUG [FTPControlSocket] 17 Jan 2014 07:48:18.251 : 125 Data connection already open; Transfer starting.
DEBUG [FTPActiveDataSocket] 17 Jan 2014 07:48:18.251 : AcceptConnection() succeeded
ERROR [FTPClient] 17 Jan 2014 07:49:20.595 : Caught exception Unable to write data to the transport connection: A connection attempt failed because the connected party did not properly respond after a period of time, or established connection failed because connected host has failed to respond.

NOTE 1: This doesn't exception does not always occur; sometimes the file will be uploaded correctly without exception error above. Full log of when it worked correctly and when it did not work are included below. Usually it fails - more than 9 out of 10 times.

NOTE 2: FileZilla client and WinSCP both work perfectly every time with same file uploading to same directory!

NOTE 3: I ripped out all the EnterpriseDT .NET stuff from my program and put replaced it with built in FtpWebRequest client - Works Perfect every time uploading to same directory!

To be completely honest I'm not real happy with EnterpriseDT right now - I just spent 4 days trying to fix a EnterpriseDT .NET problem; desperately trying to determine what I did wrong.



So below is your detailed log file where you can see where EnterpriseDT .NET worked the day before and then where it did not work the next day:

16 Jan 2014 File Upload succeeds...


DEBUG [FTPConnection] 16 Jan 2014 17:54:28.943 : Set LocalDirectory='C:\DynamicJobs\SV_NYSE'
DEBUG [FTPClient] 16 Jan 2014 17:54:28.943 : Connecting to 172.16.7.137:21
DEBUG [HostNameResolver] 16 Jan 2014 17:54:28.990 : Resolving 172.16.7.137
DEBUG [HostNameResolver] 16 Jan 2014 17:54:28.990 : 172.16.7.137 resolved to 172.16.7.137
INFO [BaseSocket] 16 Jan 2014 17:54:28.990 : Connecting to 172.16.7.137:21 with timeout 60000 ms
DEBUG [BaseSocket] 16 Jan 2014 17:54:29.084 : Successfully connected to 172.16.7.137:21
DEBUG [FTPControlSocket] 16 Jan 2014 17:54:29.100 : Setting socket timeout=60000
INFO [FTPControlSocket] 16 Jan 2014 17:54:29.115 : Command encoding=System.Text.SBCSCodePageEncoding
DEBUG [FTPControlSocket] 16 Jan 2014 17:54:29.115 : StrictReturnCodes=False
DEBUG [FTPControlSocket] 16 Jan 2014 17:54:29.131 : 220 Microsoft FTP Service
DEBUG [FTPConnection] 16 Jan 2014 17:54:29.147 : Connected to 172.16.7.137 (instance=0)
DEBUG [FTPControlSocket] 16 Jan 2014 17:54:29.193 : ---> USER SV-North
DEBUG [FTPControlSocket] 16 Jan 2014 17:54:29.240 : 331 Password required for SV-North.
DEBUG [FTPControlSocket] 16 Jan 2014 17:54:29.240 : ---> PASS ********
DEBUG [FTPControlSocket] 16 Jan 2014 17:54:29.287 : 230 User logged in.
DEBUG [FTPConnection] 16 Jan 2014 17:54:29.287 : Successfully logged in
DEBUG [FTPControlSocket] 16 Jan 2014 17:54:29.287 : ---> FEAT
DEBUG [FTPControlSocket] 16 Jan 2014 17:54:29.334 : 211-Extended features supported:
DEBUG [FTPControlSocket] 16 Jan 2014 17:54:29.334 : LANG EN*
DEBUG [FTPControlSocket] 16 Jan 2014 17:54:29.334 : UTF8
DEBUG [FTPControlSocket] 16 Jan 2014 17:54:29.334 : AUTH TLS;TLS-C;SSL;TLS-P;
DEBUG [FTPControlSocket] 16 Jan 2014 17:54:29.334 : PBSZ
DEBUG [FTPControlSocket] 16 Jan 2014 17:54:29.334 : PROT C;P;
DEBUG [FTPControlSocket] 16 Jan 2014 17:54:29.334 : CCC
DEBUG [FTPControlSocket] 16 Jan 2014 17:54:29.334 : HOST
DEBUG [FTPControlSocket] 16 Jan 2014 17:54:29.334 : SIZE
DEBUG [FTPControlSocket] 16 Jan 2014 17:54:29.334 : MDTM
DEBUG [FTPControlSocket] 16 Jan 2014 17:54:29.334 : REST STREAM
DEBUG [FTPControlSocket] 16 Jan 2014 17:54:29.334 : 211 END
DEBUG [FTPControlSocket] 16 Jan 2014 17:54:29.334 : ---> TYPE I
DEBUG [FTPControlSocket] 16 Jan 2014 17:54:29.381 : 200 Type set to I.
DEBUG [FTPControlSocket] 16 Jan 2014 17:54:29.381 : ---> PWD
DEBUG [FTPControlSocket] 16 Jan 2014 17:54:29.428 : 257 "/" is current directory.
DEBUG [FTPControlSocket] 16 Jan 2014 17:54:29.428 : ---> TYPE I
DEBUG [FTPControlSocket] 16 Jan 2014 17:54:29.475 : 200 Type set to I.
DEBUG [FTPConnection] 16 Jan 2014 17:54:29.475 : ChangeWorkingDirectory('/playlist/N-G7')
DEBUG [FTPControlSocket] 16 Jan 2014 17:54:29.475 : ---> CWD /playlist/N-G7
DEBUG [FTPControlSocket] 16 Jan 2014 17:54:29.522 : 250 CWD command successful.
DEBUG [FTPControlSocket] 16 Jan 2014 17:54:29.522 : ---> PWD
DEBUG [FTPControlSocket] 16 Jan 2014 17:54:29.584 : 257 "/playlist/N-G7" is current directory.
DEBUG [FTPControlSocket] 16 Jan 2014 17:54:29.584 : ---> FEAT
DEBUG [FTPControlSocket] 16 Jan 2014 17:54:29.631 : 211-Extended features supported:
DEBUG [FTPControlSocket] 16 Jan 2014 17:54:29.631 : LANG EN*
DEBUG [FTPControlSocket] 16 Jan 2014 17:54:29.631 : UTF8
DEBUG [FTPControlSocket] 16 Jan 2014 17:54:29.631 : AUTH TLS;TLS-C;SSL;TLS-P;
DEBUG [FTPControlSocket] 16 Jan 2014 17:54:29.631 : PBSZ
DEBUG [FTPControlSocket] 16 Jan 2014 17:54:29.631 : PROT C;P;
DEBUG [FTPControlSocket] 16 Jan 2014 17:54:29.631 : CCC
DEBUG [FTPControlSocket] 16 Jan 2014 17:54:29.631 : HOST
DEBUG [FTPControlSocket] 16 Jan 2014 17:54:29.631 : SIZE
DEBUG [FTPControlSocket] 16 Jan 2014 17:54:29.631 : MDTM
DEBUG [FTPControlSocket] 16 Jan 2014 17:54:29.631 : REST STREAM
DEBUG [FTPControlSocket] 16 Jan 2014 17:54:29.631 : 211 END
DEBUG [FTPConnection] 16 Jan 2014 17:54:29.631 : UploadFile(C:\DynamicJobs\SV_NYSE\_SV-NYSE-dyn.qti,_SV-NYSE-dyn.qti,False)
DEBUG [FTPControlSocket] 16 Jan 2014 17:54:29.631 : ---> SIZE _SV-NYSE-dyn.qti
DEBUG [FTPControlSocket] 16 Jan 2014 17:54:29.694 : 550 The system cannot find the file specified.
DEBUG [FTPControlSocket] 16 Jan 2014 17:54:29.694 : Expected reply codes = [213] (strict=False)
WARN [FTPConnection] 16 Jan 2014 17:54:29.694 : Could not get size of file _SV-NYSE-dyn.qti - 550 The system cannot find the file specified. (code=550)
DEBUG [FTPConnection] 16 Jan 2014 17:54:29.694 : GetLastWriteTime(_SV-NYSE-dyn.qti)
DEBUG [FTPControlSocket] 16 Jan 2014 17:54:29.694 : ---> MDTM _SV-NYSE-dyn.qti
DEBUG [FTPControlSocket] 16 Jan 2014 17:54:29.740 : 550 The system cannot find the file specified.
DEBUG [FTPControlSocket] 16 Jan 2014 17:54:29.740 : Expected reply codes = [213] (strict=False)
DEBUG [FTPConnection] 16 Jan 2014 17:54:29.740 : Could not retrieve modified-time of file _SV-NYSE-dyn.qti - 550 The system cannot find the file specified. (code=550)
DEBUG [FTPConnection] 16 Jan 2014 17:54:29.772 : Cancel resume
DEBUG [FTPControlSocket] 16 Jan 2014 17:54:29.772 : ---> REST 0
DEBUG [FTPControlSocket] 16 Jan 2014 17:54:29.819 : 350 Restarting at 0.
DEBUG [FTPControlSocket] 16 Jan 2014 17:54:29.850 : NewActiveDataSocket(0)
DEBUG [FTPControlSocket] 16 Jan 2014 17:54:29.897 : ---> PORT 172,16,50,15,16,229
DEBUG [FTPControlSocket] 16 Jan 2014 17:54:29.944 : 200 PORT command successful.
DEBUG [FTPControlSocket] 16 Jan 2014 17:54:29.959 : Next active port will be: 19041
DEBUG [FTPControlSocket] 16 Jan 2014 17:54:29.959 : ---> STOR _SV-NYSE-dyn.qti
DEBUG [FTPControlSocket] 16 Jan 2014 17:54:30.006 : 125 Data connection already open; Transfer starting.
DEBUG [FTPActiveDataSocket] 16 Jan 2014 17:54:30.022 : AcceptConnection() succeeded
DEBUG [FTPClient] 16 Jan 2014 17:54:34.210 : Closing source stream
DEBUG [FTPClient] 16 Jan 2

Answer 1

The most likely reason for the failure is your local firewall (especially since it worked on one day but not the next). Try disabling it temporarily or adding an exception for your program.

Answer 2

There is no firewall, it has been disabled; and even if there was a firewall that was causing the problem it doesn't explain why FileZilla, WinSCP, and FtpWebRequest all work every day and every time I try them. It is something wrong with EnterpriseDT.

Answer 3

Have you tried using passive mode? It's more firewall friendly.

- Hans (EnterpriseDT)