You run an
ipconfig and find that your IP address is 169.254.x.x with no default gateway and no access to the internet. This means that your computer was trying to find a DHCP server, but couldn’t, so it gave itself an IP. This is known as an APIPA Address. Definiition: (Automatic Private IP Addressing) The Windows function that provides DHCP autoconfiguration addressing. APIPA assigns a class B IPaddress from 169.254.0.0 to 169.254.255.255 to the client when a DHCP server is either permanently or temporarily unavailable.
You need to check the cabling to the workstation. Reseat the ethernet cable on both ends. Verify that the port it is plugged in to is lit up on the switch.
ncpa.cpl. What does it say as the status? Connected? Network Cable Unplugged? If the latter, resolve that first. If the computer is on DHCP, try assigning it a static IP and switch back to DHCP. Also try disabling IPv6 just for troubleshooting, you can re-enable later.
You need power cycle the modem, switch, and router. Get logged in to another computer on the network and find out the default gateway by running an
Log in to the default gateway’s web gui, and see if it can see the computer with the 169.254 address at all. Look by the name of the computer (the NetBios name => found by using the keyboard shortcut Win + Pause/ Break).
If the router can see the computer, go to it and try this: