There is A HP, Dell, and a Compaq the Compaq can access both of the other two computers. The Dell and HP can access each other but they cant access the Compaq because it says "\\Walker is not accessible. You might not have permission to use this network resource. Contact the administrator of this sever to find out if you have access permissions."
How do I make it accessible I don't think I have did anything?
More aboutnetwork hard drive
First, turn off your firewall and see if that's the problem. If it is you'll have to change the security settings. If not, you'll have to change the security settings of the OS.