The most likely cause for this condition is having recently used an external monitor with your PC.
If you use an external monitor with Unity and disconnect the monitor while the application is still open, the software will appear
to fail when you launch the Data selection screen in your next Unity session. Unity is still directing its GUI to the extended
monitor and will continue to do so until its brought back to the native PC
After you get to the 'frozen' condition, Select ALT & SPACE then M. This will allow you to use the arrow keys move the window into view.
If you use an external monitor with Unity and disconnect the monitor while the application is still open, the software will appear
to fail when you launch the Data selection screen in your next Unity session. Unity is still directing its GUI to the extended
monitor and will continue to do so until its brought back to the native PC
After you get to the 'frozen' condition, Select ALT & SPACE then M. This will allow you to use the arrow keys move the window into view.