can't even start it
Same here
deleted contents in AppData/Roaming again (except the .conf), works now. I might have broken it when exiting by killing the process when it seemed unresponsive.
I had this error also, I deleted all but the .conf file, restarted and NeoCoin starts, but when I click on the Mining button, I get taken to the NeoCoin page via Internet Explorer (most annoying error)
I shut down, deleted every thing including the conf file re-start and again the mining button launches Internet Explorer - with no other clue am watching the block counter ticking higher and high while I fade away.