I can't get any network connection
This is likely to be a cabling issue.
Please check that your ethernet cable is connected into the back of the PC and the network port is connected to the floor.
You may need to try a different network port on the floor, if there is another one available.
For further support fixing cable issues, check: https://help.it.ox.ac.uk/helpcentre/troubleshooting/intro/index
Otherwise, please contact Russell Dean for support.