Close the wallet, go to %appdata%\MemoryCoin , save your wallet.dat as backup, delete everything except wallet.dat and try restarting the client
If this doesn't help, try following these steps: https://bitsharestalk.org/index.php?topic=2828.msg35234#msg35234

The wallet worked fine yesterday but today when starting, it gets stuck on "Loading wallet...". Does this have something to do with the newly released wallet? And how can I fix it?

I have quite a bit of coins on it and I'd hate to lose them.

Kind regards