First, wait a few minutes and try again.
Second, figure out whether Blackboard is down, or whether the problem is elsewhere – perhaps in your network connection, or a campus-wide computing problem such as authentication or myUMBC.
If you usually go to Blackboard through myUMBC, try going to https://blackboard.umbc.edu directly. It could be that myUMBC is having a problem but NOT Blackboard.
Try using your web browser to connect to google.com. If you can't, then the problem is in your connection to the Internet. If you can, next try connecting to other UMBC systems (e.g. http://gmail.umbc.edu or http://my.umbc.edu). If you can't connect to other systems then the problem isn't with Blackboard alone, and you should contact Technology Support to alert them to the problems.