.NET SFTP Library

Do you want the best in security, reliability, and performance for SSH? Buy the .NET SFTP Library from Kellerman Software. The component supports public key authentication and private key authentication using passphrases. OpenSSH, Putty, and IETF formats can be used. Proxy servers are also supported. The .NET SFTP Library excels at handling intermittent network connections. The .NET SFTP Library is the only component available where you can unplug the cable in the middle of a transfer, plug it back in, and it resumes automatically where it left off. The .NET SFTP Library is the only one that can calculate the time difference between two servers to perform an ultra fast directory tree synchronization. Competitor libraries use the file size, which could actually miss updated files with the same size. It supports all .NET project types including .NET Framework .NET Core, Mono, Xamarin iOS, Xamarin Mac, Xamarin Android, UWP, Unity, .NET 5, and .NET 6. It can be used with any .NET language including VB.NET and C#. Why pay more for another SFTP library that is less reliable and has less features? Download the full list of features.

We also have a library to perform FTP over SSL. An FTP Adapter is included that allows you to use both components from the same interface. Use the discount code FTPANDSFTP to get a discount when purchasing both.

While it can be purchased separately, this product is also included in the Gold Suite. Gold Suite subscribers receive all product updates and all new products as part of a yearly subscription. It is the best value in the industry.

Features

How does the .NET SFTP Library stack up against the competition?

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• Full working version
• Includes technical support
• Compatible with Windows, macOS, Linux, iOS, Android and Docker.
• Compatible with .NET Framework 4.5 and higher, .NET Core 2.0 and higher, Mono 5.4 and higher, Xamarin.iOS 10.14 and higher, Xamarin.Mac 3.8 and higher, Xamarin.Android 8.0 and higher, Universal Windows Platform 10.0.16299 and higher, Unity 2018.1 and higher, .NET 5, and .NET 6.

Download Options

• Download Full Installer (Includes Help File)
• Download Zip No Installer (Includes Help File)
• Download NuGet Package (No Help File)
• Online Help

The .NET SFTP Library requires the following system configuration.

• Compatible with Windows, macOS, Linux, iOS, Android and Docker.
• Compatible with .NET Framework 4.5 and higher, .NET Core 2.0 and higher, Mono 5.4 and higher, Xamarin.iOS 10.14 and higher, Xamarin.Mac 3.8 and higher, Xamarin.Android 8.0 and higher, Universal Windows Platform 10.0.16299 and higher, Unity 2018.1 and higher, .NET 5, and .NET 6.

//Example of connecting with public key authentication then uploading a file
 
SFTP sftp = new SFTP(); //Trial Mode            
//SFTP sftp = new SFTP("place user name here", "place license key here");
 
// set the name of the SSH server( its URL )
sftp.HostAddress = "some.sftp.server.com"; // replace with your SFTP server
sftp.UserName = "anonymous"; // replace with your user name
sftp.Password = "user@mail.com"; // replace with your password
 
sftp.Connect();
sftp.UploadFile("c:\\uploadfile1.txt", "uploadfile1.txt");
sftp.Disconnect();
 
//Example of connecting with public/private key authentication with a passphrase then uploading a file
SFTP sftp = new SFTP(); //Trial Mode            
//SFTP sftp = new SFTP("place user name here", "place license key here");
 
// set the name of the SSH server( its URL )
sftp.HostAddress = "some.sftp.server.com"; // replace with your SFTP server
sftp.UserName = "anonymous"; // replace with your user name
sftp.Password = "user@mail.com"; // replace with your password
sftp.SshKeyFile = "c:\\privatekey";
sftp.SshPassphrase = "secret";
 
sftp.Connect();
sftp.UploadFile("c:\\uploadfile1.txt", "uploadfile1.txt");
sftp.Disconnect();

Q: How do I use my license key?
A: SFTP sftp = new SFTP("my user name","my license key");

Q: I lost my license key how do I retrieve it?
A: Go to your account

Q: I lost my software how do I retrieve it?
A: Go to downloads

Q: Where can I download the latest version of my software?
A: Click the download tab.

Q: How does the licensing work?
A: Each developer that uses the SFTP library must have a license. You may distribute your application to end users royalty free or use it on an unlimited number of servers. A site license is for all the developers in a single building. An enterprise license would be for entire company.

Q: Does the SFTP libary work with ASP.NET?
A: Yes, the SFTP libary works with .NET project type.

Q: I want to integrate the objects into my web based backend, is this possible?
A: Yes, you can use the SFTP object with an ASP.NET back end, provided the SFTP ports are allowed through by the web server firewalls.

Q: My company has 6 servers and 20 websites to synchronize, how does the licensing work? If we buy a license can I distribute it throughout all of our company websites?
A: The SFTP .NET component is licensed on a per developer basis. If you are the only developer you may certainly use it on all 20 of your websites.

Q: Our current SFTP .NET component has a file size limit of 2GB. What is the file size limit for Kellerman .NET SFTP?
A: The file size limit is 9ZB ( Zetabytes).

Q: What happens when the trial expires?
A: An exception is thrown, indicating that the trial is expired.

Q: Is Kellerman SFTP compatible with .NET 4.0 and .NET 4.5.1?
A: Kellerman SFTP is compatible with .NET 2.0 and higher.

Q: Is Kellerman SFTP compatible with Windows Server 2008?
A: Kellerman SFTP is compatible with Windows 98SE, Windows ME, Windows XP, Windows 2000, Windows Server 2000, Windows Server 2003, Windows Server 2008, Windows Server 2012, Windows Server 2016, Windows Vista, Windows 7, and Windows 8, Windows 10, Windows 11

Q: Is Kellerman SFTP thread safe?
A: An instance of Kellerman SFTP is required for each thread. Individual instances are thread safe.

Q: Is the directory synchronization feature recursive?
A: Yes, all directories, subdirectories, and files are synchronized.

Q: I am getting the error "Could not resolve host name" how do I fix this?
A: The ASPNET account may not have access to your DNS server. Try using either the internal IP Address or external IP address of the SFTP Server.

Q:I am getting the exception AUTH FAIL. What do I do?
A: Try connecting with Filezilla on the same PC. Verify the user name and password are correct. Some financial institutions require a private key and a blank password. Contact the owner of the SFTP server, ensure your IP Address is allowed through for your PC or Server.

Q: What key exchanges are supported?
curve25519-sha256
curve25519-sha256@libssh.org
diffie-hellman-group14-sha1
diffie-hellman-group14-sha256
diffie-hellman-group16-sha512
diffie-hellman-group1-sha1
diffie-hellman-group-exchange-sha1
diffie-hellman-group-exchange-sha256
ecdh-sha2-nistp256
ecdh-sha2-nistp384
ecdh-sha2-nistp521

Q: What Macs are supported?
hmac-md5
hmac-md5-96
hmac-sha1
hmac-sha1-96
hmac-sha2-256
hmac-sha2-256-96
hmac-sha2-512
hmac-sha2-512-96

Q: What Ciphers are supported?
3des-cbc
aes128-cbc
aes128-ctr
aes192-cbc
aes192-ctr
aes256-cbc
aes256-ctr
arcfour
arcfour128
arcfour256
blowfish-cbc
cast128-cbc
twofish128-cbc
twofish192-cbc
twofish256-cbc
twofish-cbc

Q: I am getting the error: Permission denied (publickey). with Ubuntu
Enable RSA. Add these two lines to your /etc/ssh/sshd_config file. Also see this answer
HostKeyAlgorithms +ssh-rsa
PubkeyAcceptedKeyTypes +ssh-rsa