That yahoo email did work via the web page but you may have been trying for POP mail (but I couldn't tell from your post.) Yahoo has PAY email which you get POP mail. The freebie doesn't have such.
I recently bought an Acer Aspire One netbook with o/s Linpus Linux Lite. I set up an email account in Yahoo but when I try adding it to Aspire One email accounts the system tries verifying the email server for about a minute and then returns the message that it is unable to access the email server.
However, my wife and I have had standard Yahoo email accounts for about 6 months and I could add both of these to the Aspire email accounts without any problems.
Because the system doesn't recognise the email account, I can't set up the Messenger either.
I would appreciate any help with this.