This article describes how to configure NetScaler EPA scan to look for a registry key with spaces.
NetScaler Gateway 10.5 requires Classic Client Security Expression to use \\ for spaces in the registry key.
For example - CLIENT.REG('HKEY_LOCAL_MACHINE\\\\SOFTWARE\\\\Microsoft\\\\SMS\\\\Client\\\\Internet\\ Facing_Internet\\ MP\\ Hostname').VALUE == www.example.com
Use HKEY_LOCAL_MACHINE_64 (for 64x bit).