Anyone else get :
Alias:mn1
Failed to start masternode.
Error: could not allocate vin
I got similar error on other master node coin, generating new key (masternode genkey) and replacing the old one, solved the issue.
Btw guys, I figured out the reason for this error. It is because when you have a masternode and you withdraw some coins, all the coins get mixed and then the original transaction to the masternode address gets bothered. I found this great video from DASH about locking your masternode coins. And when I did that, I did not get these errors anymore because essentially the coins for the masternode are locked from the rest of your wallet balance. Here is the link:
https://support.node40.com/hc/en-us/articles/115000416428-Withdraw-rewards-from-a-masternodeHope this helps