After you set the Telnet Client to send CRLF (Carriage Return Line Feed), it sends only CR.
To resolve this issue, set the Telnet Client to send CRLF after you establish a Telnet session. To do this, follow these steps:
Start the Telnet Client.
Open a Telnet session to a Telnet server.
Press CTRL+] to switch to command mode.
Type set crlf.
Press ENTER to return to session mode.
Now the Telnet Client will send both CR and LF to the server. However, you will not be able to open another session in the present Telnet session.
Microsoft has confirmed that this is a problem in the Microsoft products that are listed at the beginning of this article.
Until the Telnet connection is established (that is, until the authentication is over), the Telnet session requires only CR, irrespective of the CRLF setting.
If you set the CRLF option before authentication, the Telnet Client will send LFs when they are not appropriate. For example, after you type a user name and press ENTER, the following sequence is sent:
The following sequence should be sent:
The result is that the password now becomes "LF+password", which causes the logon process to be unsuccessful.