I tried this "walletpassphrase YOUR_PASSWORD 9999999 true" in console but says error. Also I Have not set any password as there is no conf file in there. What should I do in order to get minting
You and I have the same question
Hope someone can help us answer
Wish us luck

Think the wallet is already unlocked if you've not set any password so you shouldn't need to run this command.
On wallet main screen look at the padlock symbol in bottom right, if it's open each time you start the wallet then I think it's already unlocked but I'm open to correction on this.