With update 188.8.131.52-us Yahoo messenger has additional issues with negotiating a handshake with ISA server. Please read this KB article http://support.microsoft.com/kb/309347 for additional IE setting changes in order to let yahoo through ISA server.
Do you “still” IM using yahoo messenger? The latest version has facebook integration and more to offer which allows you to communicate (chat) with your friends online over social networks.
However, Yahoo messenger fails to establish a connection to it’s servers if behind ISA firewall. Here we are offering you some guidelines dealing with such scenarios.
Most acceptible reasoning for connectivity issues behind ISA firewall should be, YM failing to forward the NTLM authentication credentials to ISA fiewall while trying to establish a connection. Once failed to establish a connection, user will be provided a chance to troubleshoot the issue, which does the trick!
All you need to do is to click the troubleshoot button and wait for the process to complete. If curious, click on the details button to see multiple connectivity checks performed by YM. As soon as the troubleshoot activity completed, rush to login again with your username and password
You should able to logon to yahoo services without troubles this time. Please note, you should try to logon immediately once after the troubleshooting process is completed. This means you cannot wait minutes after the troubleshoot activity is completed. Else you will once again have to go through the entire process of troubleshooting until you manage to logon.
Enjoy all new features offered by Yahoo Messenger from “work” now