I think you might've deleted the wrong folder...what happened when you tried to open LW? Try uninstalling your LW (start > all programs > limewire > use the uninstall option) & then reinstall.
Make sure to download the offline installer. when you click to download LW, cancel the dialog box which pops up. Now choose the option to sownload the offline installer
Lime Wire » Download LimeWire

When you delete the preferences folder, it's the folder called LimeWire within Application Data. To check that it's the right folder, double click on it & when it's open you'll see things like this.


Did you make sure that LW was closed before you deleted the prefs folder?
Try doing it again. If none of the other fixes in that thread help, you can try port forwarding for your router. The instructions are here.
Port Forwarding for the Westell C90-610030-06
Don't forget to set up a staic IP address first, or port forwarding won't work. LW's listening port, port in the 'manual port forward' box & port forwarded within the router should all be the same number.