Turning On a Stubborn Network Discovery

On my Server 2008 virtual machine, there were some exercises that required Network Discovery to be on. However, whenever I tried to turn Network Discovery on in the Network Settings page, it simply wouldn't turn on. I could check the radio button and click apply, it would process that for a bit, then close the submenu as if it had turned it on, but the light would be gray, not green. I searched the internet for hours, turning on services, opening ports, disabling the firewall (this turned on network discovery, but besides being a security risk also made other configuration problems) but nothing I tried worked. I was at my wit's end.

Then I stumbled across this obscure thread on Microsoft's Technet, in which the last poster described a stupidly simple way to fix this. I tried it, and it worked like magic.

Other members of the class having the same problem tried it, and it worked only after turning on several services mentioned in other threads, notably, DNS Client, Workstation, Server, SSDP Service, and Remote Procedure Call.

Edit: After doing this, I was unable to turn on printer sharing. It was acting the same way as Network Discovery had been. I discovered that somehow, I had lost access to the printer! When I right clicked on the printer and selected Properties, it displayed the warning "You do not have access to this printer. Only the Security tab will be displayed." As I was logged in as Administrator, which was the account that had added the printer, I was a bit confused how that came about. I finally got around it by granting "Everyone" full control to the printer. Since that was insecure, I then deleted it and re-added the printer. I was then able to enable printer sharing in the Network and Sharing Center.