Final answer:
After confirming the printer's power and connection, the technician should verify the print queue on the server to resolve issues affecting all users.
Step-by-step explanation:
Once a technician has confirmed that the shared printer is powered on and connected to the network, the next step should involve verifying the print queue on the server. This is because any issues in the print queue such as stuck jobs or errors can prevent all users from being able to print successfully. It's a central point that can affect multiple users, making it a sensible next step before considering issues that might only affect individual users such as network cables or printer drivers.