A user from the sales department calls to report that he is experiencing problems connecting to the sales file server. All users in the sales department connect to the sales server through a single Ethernet switch. No other users have reported problems connecting to the sales server. Which of the following troubleshooting actions are you most likely to perform first?
a. Reinstall the network card drivers on the sales server.
b. Replace the network card in the user's computer.
c. Replace the Ethernet switch in the sales department.
d. Replace the network card in the sales server.