What it does:
Lookup by System Id is a simple plug-in that allows the user to provide a file of constituent system ids and lookup the corresponding constituent. Then import id which it appends to a copy of the input file.
Download the zip file and unzip the contents to a known location. Run the Setup.exe file to install the program.
To uninstall this plug-in go to the Control Panel, Add and Remove Programs and select the plug-in.