Q/A 30-Oct-2019

Question: I updated from an older version of Chilkat to the latest version, and the following CkFtp2 (C++) methods no longer exist:  GetLastAccessDt and GetLastAccessDtByName.  What happened to them? Answer: These methods were deprecated a while ago, and were finally removed.  I’ll explain.  (The methods still exist in the ActiveX because it’s not possible to remove methods in the ActiveX […]

Ftp2 AuthTls, AuthSsl, and Ssl Properties Clarified

Question: We are about using Chilkat C++ library for an FTPS connection.  I read on online documentation that there is method CkFtp2::put_AuthTls which allows setting TLS connection. Some questions about client behavior according to this method: if we don’t call this method, transmission is in clear text? Is it equivalent to CkFtp2::put_AuthTls(false)? If  we call this method with parameter true […]

Binary vs Text Transfers (SFTP / FTP)

This post clarifies the topic of binary vs. ascii uploads/downloads for SFTP (Secure File Transfer over SSH) and FTP. Binary mode transmits bytes exactly as-is.   Text mode (also known as “ascii” mode) can modify line endings (CR’s and LF’s) to the canonical convention used on the remote system.  For example, Linux systems typically use bare LF line-endings, whereas text […]

Damn You Windows Firewall!

One particular cause of the following error is finally known: sockRecv(47ms): WindowsError: An existing connection was forcibly closed by the remote host. WindowsErrorCode: 0x2746 numBytesRequested: 5 Failed to receive data on the TCP socket –sockRecv sockRecv failed. sockRecvN_buf: Did not receive the exact number of bytes desired. numBytesToReceive: 5 This error was caused by the Windows Firewall doing stateful FTP […]

v9.4.1.43 Fixed FTP2 XCRC Problem

Fixed an FTP2 XCRC issue. If the AutoXcrc property was turned on, Chilkat FTP2 was not computing the CRC of the local file (or data) uploaded to the server. This caused the CRC comparison to fail after the XCRC command was issued. Note: This fix only applies when using AutoXcrc in conjunction with a server that actually supports XCRC. This […]


Clarification on the acronyms “SFTP” and “FTPS” “SFTP” is the Secure File Transfer Protocol over SSH.  It is a protocol unrelated to the FTP protocol. (It is actually a subsystem of SSH.)  The Chilkat SSH / SFTP component is used for “SFTP”.  SFTP is achieved by connecting to an SSH server at port 22. On the other hand, the Chilkat […]