FTP, GetResponse (), error 550 File unavailable

问题:

I have created a small windows forms application to upload the file to one of our client's ftp site. But the problem that I'm having is that when I run this application on my local machine it uploads the file successfully. But if I run this program on our server, I get this error message;

remote server returned an error: (550) File unavailable (eg, file not found, can not access the file), on this line 'objFTPRequest.GetRequestStream();'.

Does anybody know why? Do I need to configure the firewall or something? Here is my code;

FileInfo objFile = new FileInfo(filename);
FtpWebRequest objFTPRequest;

// Create FtpWebRequest object 
objFTPRequest = (FtpWebRequest)FtpWebRequest.Create(new Uri("ftp://" + ftpServerIP + "/outbox/" + objFile.Name));

// Set Credintials
objFTPRequest.Credentials = new NetworkCredential(ftpUserName, ftpPassword);

// By default KeepAlive is true, where the control connection is 
// not closed after a command is executed.
objFTPRequest.KeepAlive = false;

// Set the data transfer type.
objFTPRequest.UseBinary = true;

// Set content length
objFTPRequest.ContentLength = objFile.Length;

// Set request method
objFTPRequest.Method = WebRequestMethods.Ftp.UploadFile;

// Set buffer size
int intBufferLength = 16 * 1024;
byte[] objBuffer = new byte[intBufferLength];

// Opens a file to read
FileStream objFileStream = objFile.OpenRead();


// Get Stream of the file
Stream objStream = objFTPRequest.GetRequestStream();

int len = 0;

while ((len = objFileStream.Read(objBuffer, 0, intBufferLength)) != 0)
{
    // Write file Content 
    objStream.Write(objBuffer, 0, len);

}

            objStream.Close();
            objFileStream.Close();

回答1:

This error can be caused because of several reasons like file is not present on server, security permissions on file etc. etc.

First you need to find out the exact cause of error. This can be achieved by using following code-

try
{
        //Your code
}
catch(WebException e)
{
        String status = ((FtpWebResponse)e.Response).StatusDescription;
}

Once you get the exact cause of error, you can go forward to solve it.

Here are some links you can refer

http://forums.asp.net/t/1777881.aspx/1

http://nickstips.wordpress.com/2010/10/25/c-ftp-upload-error-the-remote-server-returned-an-error-550-file-unavailable-e-g-file-not-found-no-access/

http://www.dreamincode.net/forums/topic/76361-file-upload-to-server/

http://forums.asp.net/t/1374306.aspx/1

回答2:

Try this: ftp://xxx.xxx.xx.xx:21//path/filename

The "//" after the server address starts you out at the root directory. Even though I had: ftp://xxx.xxx.xx.xx:21/path/filename, it didn't take me to the correct directory.

回答3:

I met the same problem, and this is what I did:

1. Check the OS has the right to write. Find the ftp folder =>right click=>properties=>security, then you must know what you should do
2. Check the ftp server open the write right to the user you logged. Open IIS=>click the ftp site=>ftp Authorization Rules=>add allow rules=>choose a user or group to set the rights
3. Check the the dir on the ftp server, do the same thing on item 2.

I can use four pictures to show the rights to be set:

回答4:

It could be more simple.

I facing similar issue and i tried all the suggested solution but no one work. I'm figure out in simple manner like this one : take a look

Wrong code at my end

 Dim request As Net.FtpWebRequest = CType(FtpWebRequest.Create("ftp://xxx.xxx.xxx.xxx/files"), FtpWebRequest)

Change it in this simple one :

 Dim request As Net.FtpWebRequest = CType(FtpWebRequest.Create("ftp://xxx.xxx.xxx.xxx/files/youfilename.ext"), FtpWebRequest)

then procced with fill request and send to server :)

That's all.

Make sure that all permission on server work fine and u're using right credential.

回答5:

In order to resolve this issue, it is required to force the System.Net.FtpWebRequest command to revert back to the old behavior of how it used to work in .Net Framework 2.0/3.5 and issue the extra CWD command before issuing the actual command.

In order to do this, the following code needs to be placed before any instance of the System.Net.FtpWebRequest class is invoked. The code below only needs to be called once, since it changes the settings of the entire application domain.

private static void SetMethodRequiresCWD()
{
        Type requestType = typeof(FtpWebRequest);
        FieldInfo methodInfoField = requestType.GetField("m_MethodInfo", BindingFlags.NonPublic | BindingFlags.Instance);
        Type methodInfoType = methodInfoField.FieldType;


        FieldInfo knownMethodsField = methodInfoType.GetField("KnownMethodInfo", BindingFlags.Static | BindingFlags.NonPublic);
        Array knownMethodsArray = (Array)knownMethodsField.GetValue(null);

        FieldInfo flagsField = methodInfoType.GetField("Flags", BindingFlags.NonPublic | BindingFlags.Instance);

        int MustChangeWorkingDirectoryToPath = 0x100;
        foreach (object knownMethod in knownMethodsArray)
        {
            int flags = (int)flagsField.GetValue(knownMethod);
            flags |= MustChangeWorkingDirectoryToPath;
            flagsField.SetValue(knownMethod, flags);
        }
 }

http://support.microsoft.com/kb/2134299

回答6:

When i had the same issue i tried everything above and after a day later i realize that the path which i created for uri having a white space in between "/" and the folder name

string uri="192.168.1.101/ Sync/Image.jpg";

the above string should be

string uri="192.168.1.101/Sync/Image.jpg";

this small mistake also throws the same error and it's a valid error because this is not valid path for our file if it contains any white spaces between "/" and folder/file name

回答7:

I too had this problem recently. What I found is that when I use ftpUploadFile the routine is trying to put the file in the root ftp folder. Normal command line ftp worked fine. However issuing a pwd command from the command line ftp revealed that this particular server was setting a different current directory upon login. Altering my ftpUploadFile to include this folder resolved the issue.

回答8:

Just to throw my hat in the ring, I was getting the same error. When the FTPRequest was requesting files from the FTP Service on the same computer (same IP). In the request I was using the IP address of the machine but once I changed that to 127.0.0.1 it worked. interestingly enough, requests from other IP addresses were being processed and files downloaded, just not from itself.

Hope that helped someone.

回答9:

I was having the same problem, when i compared with the ftpuri and User Name Path it is resolved When I create ftp access i have chose the path as /directory name

in the ftpuri when i included the directory name it gave the error and when i removed the directory name it is resolved.

ftpuri with error

"ftp://www.example.com/Project/yourfilename.ds"

ftpuri resolved

"ftp://www.example.com/yourfilename.ds"

ftp access folder "/Project"

回答10:

Make sure target folder "outbox" exists. That was my problem with error 550.

Simply create target directory "output" before upload.

try
        {
            WebRequest request = WebRequest.Create("ftp://" + ftpServerIP + "/outbox");
            request.Credentials = new NetworkCredential("user", "password");
            request.Method = WebRequestMethods.Ftp.MakeDirectory;
            using (var resp = (FtpWebResponse)request.GetResponse())
            {
                Console.WriteLine(resp.StatusCode);
            }
        }
        catch (WebException ex)
        {
            FtpWebResponse response = (FtpWebResponse)ex.Response;
            if (response.StatusCode == FtpStatusCode.ActionNotTakenFileUnavailable)
            {
                response.Close();
                //already exists
            }
            else
            {
                response.Close();
                //doesn't exists = it's another exception
            }
        }

回答11:

I had this problem. Filezilla was fine, .net wasn't. It was to a wordpress server. To get it working, I changed the my code from this:

ftp://XXX.XXX.XXX.XXX//folder//" + txtFile.Text

to:

ftp://[FTPNAME]@XXX.XXX.XXX.XXX//" + txtFile.Text

and it now thankfully works.

I don't know if this is specific to Wordpress FTP folders.

回答12:

In my case, there was a root folder referenced in my ftp address that was missing. After to create the folder the problem was solved.

ftp://xxx.xxx.xx.xx:21//rootfolder/

回答13:

I found the solution. The problem is the Current Working Directory of the ftp user. If you type a url like ftp:///path/test.txt it is used as a relative path ro the working directory. For example CWD is /test then the used path is /test/path/test.txt. If you want to use an absolute path, you have to type the url like ftp:////path/test.txt. Then the file is uploaded in the folder /path/test.txt, without exception.