I'm usually in a situation where my user doesn't have access to the switches and I'm 5-200 miles away. 🙂
My usual process is:
1. Find out the mac address if I can.
2. Check for that mac addr in the client list.
3. If mac addr exists, check client to see if a switchport is listed.
4. If no dice, proceed to...
See if user can trace cable and get access to switches:
1. Look at diagram of how the front of the switch looks. Practice teaching someone how to identify the port number.
2. Label your switches somehow, so you and the user can say "port 14 on switch ATL-MO-5" and understand.
3. Ask client to try port num whatever. If switchport is not shutdown, tell you if blinkenlights appear.
4. Check switchport to see if you're seeing the client, on the dashboard.
5. Adjust switchport as necessary.
6. Check for client communication again.