Yahoo doesnt have a IM client for linux so you are probably trying to
install a windows .exe file.

If you are wanting to chat online then I would suggest pidgin. Its a
client that can access google talk, aim, yahoo im and others.

Go to System > Administration > Synaptic Package Manger and do a search
for Pidgin and install it.

You can use the AOL IM (AIM) with linux or Kopete IM with the KDE
desktop or Pidgin with Gnome desktop.

And if all else fails, you can access all of the major IM systems at
http://www.meebo.com/ through your web browser. I've used it in Ubuntu
& CentOS both on Firefox.

think u can use pidgin or yahoo web im.

It sound like you are attempting to install the Windows version of
Yahoo Messenger. While Linux has quite good support for some Windows
software through Wine etc. it is by no means universal.

Several have mentionedPigin (spelling?) but my personal favourite is
Kopete, a KDE programme, with (in my limited experience) better cam
support. It's in the repositories and looks good on Gnome.

i installed Yahoo IM as a windows .exe via WINE but it wont log in
so i use Pidgin works just as well for me

I'd say Pidgin is good and used it for quite a while [installed by
default in ubuntu]. If you would like to try a web based one try Meebo
which is what i use these days.

I found that yahoo messenger wont work on ubuntu i tried to do the same
thing you did you'll have to get use to another my suggestions to you is try
pidgin or kopete they will run both msn, yahoo , AOL and icq give them a try
yahoo i guess wasn't meant for Linux unless i missed something somewhere
tried to install using wine but it gave me troubles and didn't log in to the
account.
don't know what else to tell you ubuntu is a good operating system but
theres some thing still needed to be worked on. [?]

Linux is not windoze... it is fair to say. You have to accept that a lot
will be different - some is much better and some not so good. As i said
earlier try Meebo for IM. yahoo IM is no great loss really. Pidgin is the
renamed Gaim which was a good IM client.

the issue with yahoo is usually them messing with their protocol to
interfere with third party compatibility.

I simply use yahoo messenger from my yahoo mail...but pidgen works
fine for me

There is no "ultimate authority" in Ubuntu so a variety of opinions will
always be found and even some outright contradictions! My experience has
been that Ubuntu can handle ntfs partitions just as reliably as FAT and
FAT32 onces.