I installed kmail and used the setting as given in the wiki. BUt i am not getting inbox emails at all.I can only see the trash and spam emails. I deleted theprevious accounts and configured new accounts .Still getting the same thing.
How can i enable inbox emails?

Are they POP3 or IMAP accounts?
For IMAP account, ensure that inbox folder is subscribed at server (there are two types of subscription in KMail: server and local).
I suppose you triple-checked that you have entered correct username, password, host and encryption settings.