Yahoo Messenger not showing messages!

[hollown]

Dear friends,
My yahoo messenger won't show any messages on the IM window. I can see what i am typing but not when i've sent it already. I can't also see the messages sent for me. I've already reinstall different versions of yahoo messenger and have followed the instructions to troubleshoot it but it still doesn't work for me.

Now what can i do? Please help.
Thanks in advance.