Did you try to resync the Blockchain and also try the comand:
masternode start all
in the Console ?
Which lines are in your masternode.conf & solaris.conf ?
I have running 10 MN´s without Problems.
Yes, I tried it several times. It seems that the provided set up guide is outdated or the problem is only affecting new masternodes.
I use the same schema for these two files as it provided in the guide:
ALIAS VPS_IP:60020 PRIVATE_KEY TRANSACTION_ID INDEX_ID - masternode.conf
And solaris.conf:
rpcallowip=127.0.0.1
rpcuser=ANY_LONG_USERNAME
rpcpassword=ANY_LONG_PASSWORD
staking=0
server=1
listen=1
port=60020
masternodeaddr=VPS_IP:60020
externalip=VPS_IP:60020
masternodeprivkey=PRIVATE_KEY