Since the HelpDesk is the front line to the user community, they get to deal with a lot of people who are not very technical. We have all heard the stories about users using the CDROM tray as a cup holder or the computer not turning on because of power issues. The Packet Pushers Podcast even did a two part episode (Part 1, Part 2) on IT war stories not too long ago.
Here is a story of mine. One of the tickets that the Helpdesk received from time to time was 'Slow Internet'. Of course this could be a number of issues, but this problem seemed to happen with some frequency and the whole IT department seemed to come together to solve it this time. The real symptom was that Internet Explorer or Outlook would attempt to connect and sit there for several minutes. Then they would eventually connect to the website or Exchange respectively. No other applications seemed to experience this. The Helpdesk agent did his due diligence in troubleshooting basic connectivity and found nothing. The ticket was transferred to the network team. We monitored the switchport with Solarwinds for utilization and errors. We captured packets, moved the PC to different switchports, and eventually moved the PC to a different switch, but we never found anything. The group that managed the desktops re-imaged the machine and eventually swapped out the machine itself. The security group ran captures and traces on the proxy server, but they too found nothing in the proxy server.
The security group did eventually find the source of the problem. Years before many of us worked there, someone configured in the workstation image a registry entry to automatically pull a configuration file from a web server to configure proxy server settings. That proxy server no longer existed, but that web server was still up and serving that stale configuration file. These configuration settings never showed up in any configuration screen. Anyone who was related to setting that up had long gone, but it was still there to haunt us. After a patch was applied to all workstations and the workstation images to remove the registry entry, we rarely heard of slow Internet issues again.
What is your Helpdesk war story?