Re: [ANN] Slimcoin : Proof of Burn NEW BLOCK GEN, Mineable by low power computer!
make sure that your wallet is properly synced, currently @ block 12225
I think that might currently be a problem for many 
Mine repeatedly gets stuck at 10202, with the debug.log citing "ERROR: ConnectInputs() : tried to spend coinbase/coinstake at depth 408". I've got it wiping everything restarting periodically, but might as well wait for an updated wallet with a proper fix
I had the same issue, & this is how i fixed my wallet.
1. Close Wallet
2. Delete everything in %appdata%/slimcoin EXCEPT WALLET.DAT & SLIMCOIN.CONF
3. Edit Slimcoin.conf, delete EVERYTHING and paste this :
server=1
daemon=1
rpcuser=USER
rpcpassword=PASSWD
rpcallowip=127.0.0.1
rpcallowip=192.168.1.*
rpcallowip=localhost
connect=144.76.139.111:10000
4. Be patient & let it sync COMPLETELY
5. After its done, go back to %appdata%/Slimcoin
6. Edit slimcoin.conf, delete EVERYTHING & add this :
server=1
daemon=1
rpcuser=USER
rpcpassword=PASSWD
rpcallowip=127.0.0.1
rpcallowip=192.168.1.*
rpcallowip=localhost
addnode=114.34.15.168
addnode=63.141.232.170
addnode=50.116.56.210
addnode=108.7.224.149
addnode=85.25.195.74
addnode=72.252.176.12
addnode=213.82.213.152
addnode=144.76.142.47
addnode=77.237.251.163
addnode=84.198.182.60
addnode=76.127.202.17
addnode=96.237.174.192
addnode=107.181.250.216
addnode=107.181.250.217
addnode=144.76.142.47
addnode=144.76.142.49
7. Reopen Slimcoin-QT