======Troubleshooting Tips======

=====Telnet=====
One of the most basic, and useful, tools for troubleshooting email systems is a Telnet client. 

====Installing Telnet Client====
Unfortunately, since Windows XP, Microsoft do not install the Telnet client into Windows by default, so you may need to install the Telnet client yourself.

To do this, go to ''Control Panel -> Programs and Features''.

Choose **Turn Windows features on or off** in the left pane of the window

Scroll down until you find **Telnet Client** (note do NOT install "Telnet Server", that is a security risk, unlike the Telnet Client). Check the box next to **Telnet Client** and press **OK**

You will normally not need the original installation disks to do this

====Using Telnet====
To use the Telnet client, go to ''Start -> Run'' in Windows, and type ''cmd'' and press OK

In the command prompt window that appears, type:

  Telnet <address of VPOP3 computer> <port number>
  
====Testing POP3====
  
For instance, to test the POP3 service (port 110) if VPOP3 is on 192.168.1.1, type:

  Telnet 192.168.1.1 110
  
The response should say something like:

  +OK VPOP3 Server Ready <random.text>
  
If this is the response you get then you can type

  USER <username>
followed by
  PASS <password>
  
eg
  +OK VPOP3 Server Ready <6c.16a8.4069e3ac>
  USER test
  +OK User Accepted, PASSword required
  PASS testpass
  +OK test has 23 message(s) (121552 octets)
  QUIT
  +OK VPOP3 Server Closing Connection
  
That shows a valid login attempt. Any errors received during this process will be useful diagnostic information. This is especially helpful if you are limited to using an email client such as Microsoft Outlook which usually hides errors during the logon process so you can't see the error messages generated by the server.

Note that while typing commands in this way, you cannot use the backspace or other editing keys, you must type accurately the first time. If you make a mistake it is best to start again.
  
====Testing SMTP====

SMTP is usually on port 25, and the response should say:
  
  220 <host name> VPOP3 ESMTP Server Ready

====Testing IMAP4====
IMAP4 requires VPOP3 Enterprise. The usual port for IMAP4 is port 143, and the response should say:

''* OK VPOP3 IMAP4rev1 Server''

If the VPOP3 name is not there, then this may indicate that you have another mail server on the same computer as VPOP3, which is "taking over". If the response includes error text, then you can search for that text here on the Wiki, or it will be useful information to give when you contact technical  support for help.