Telnet is not the greatest programme to use for chat. However, Vista does not have telnet enabled as default. To install it go to:
Start menu->Control Panel\Programs\Programs and Features
on left select Turn windows features on and off
After a while a box will appear = look for Telnet Client and select it and press ok
Now go to Start Menu->Programs->Accessories
select Command Prompt
enter telnet and the IP Address of the computer you wish to connect with
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However, for chat I would suggest the more traditional chat programmes.
MSN Messenger (Free from Internet)
Yahoo Messenger (Free from Internet)
ICQ Messenger (Free from Internet)
AIM Messenger (Free from Internet)
If most of your email contacts are using Hotmail then use MSN,
http://download.live.com/?sku=messenger
if they use AOL then use AIM
http://dashboard.aim.com/aim
If they use Yahoo then use Yahoo Messenger
http://uk.messenger.yahoo.com/
Otherwise use ICQ
http://www.icq.com/
Happy Chatting
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