LDMS 9.0 UDD network scan hangs

Bug?

After entering the wrong subnet mask when attempting to target a single computer for discovery via UDD; the scan gets stuck in an endless loop. Cancel Scan has no effect. Even after attempting to close window, the scan continues and window will not close.  Task Manager could not close task. Resorted to a reboot.

Network Scan Parameters:

    From            To           Subnet Mask

172.x.x.x    172.x.x.x      255.255.255.255