Index: kioslave/ftp/ftp.cc
===================================================================
--- kioslave/ftp/ftp.cc.orig
+++ kioslave/ftp/ftp.cc
@@ -1275,6 +1275,16 @@ bool Ftp::ftpRename( const QString & src
         return false;
     }
 
+  // Must check if dst already exists, RNFR+RNTO overwrites by default (#127793).
+  if (ftpFileExists(dst)) {
+      error(ERR_FILE_ALREADY_EXIST, dst);
+      return false;
+  }
+  if (ftpFolder(dst, false)) {
+      error(ERR_DIR_ALREADY_EXIST, dst);
+      return false;
+  }
+
   int pos = src.findRev("/");
   if( !ftpFolder(src.left(pos+1), false) )
       return false;
@@ -2406,6 +2416,19 @@ bool Ftp::ftpSize( const QString & path,
   return true;
 }
 
+bool Ftp::ftpFileExists(const QString& path)
+{
+  QCString buf;
+  buf = "SIZE ";
+  buf += remoteEncoding()->encode(path);
+  if( !ftpSendCmd( buf ) || (m_iRespType != 2) )
+  return false;
+
+  // skip leading "213 " (response code)
+  const char* psz = ftpResponse(4);
+  return psz != 0;
+}
+
 // Today the differences between ASCII and BINARY are limited to
 // CR or CR/LF line terminators. Many servers ignore ASCII (like
 // win2003 -or- vsftp with default config). In the early days of
Index: kioslave/ftp/ftp.h
===================================================================
--- kioslave/ftp/ftp.h.orig
+++ kioslave/ftp/ftp.h
@@ -350,6 +350,11 @@ private:
   /**
    * Set the current working directory, but only if not yet current
    */
+  bool ftpFileExists(const QString& path);
+
+  /**
+   * Set the current working directory, but only if not yet current
+   */
   bool ftpFolder(const QString& path, bool bReportError);
 
   /**