Hello All,
Welcome to the LogMeIn community.
A common solution to this issue is to restart LogMeIn on the host Mac. You can do that through LogMeIn by clicking Preferences on the left side of the page once you connect to the computer. You will then choose Advanced Settings > Reboot Options. Click the option to Reboot LogMeIn.
After about 15-30 seconds you should be able to connect again. If you still only receive a black screen after restarting LogMeIn, it would be best to contact us
Mike Peaden
Customer Support Representative
LogMeIn, Inc.