C:\Users\priyj_kumar>ping Loopback
Pinging DESKTOP-TGAB9Q5 [::1] with 32 bytes of data:
Reply from ::1: time<1ms
Reply from ::1: time<1ms
Reply from ::1: time<1ms
Reply from ::1: time<1ms
Ping statistics for ::1:
Packets: Sent = 4, Received = 4, Lost = 0 (0% loss),
Approximate round trip times in milli-seconds:
Minimum = 0ms, Maximum = 0ms, Average = 0ms
If the ping is successful, then, the TCP/IP stack is good.
If the ping was not successful, then, you will have to reinstall the TCP/IP stack in the user's computer.