In Terminal Services, some files may not open correctly when more than one user tries to use them. These programs must be run in a system or user global context to function correctly.
When you open a CMD prompt and type register /?, you receive:
Register a program so it can have special execution characteristics.
REGISTER filename \[/SYSTEM | /USER\] \[/V\]
/SYSTEM Register filename as SYSTEM GLOBAL resource.
/USER Register filename as USER GLOBAL resource.
/V Provides verbose information.
NOTE: "Registration data for a program is recognized only when the program is installed. If you issue a register command for a program that is already installed, the changes take effect the next time the program is installed".