Citrix "Error adding custom ICA connection"

So you load the latest Citrix client on three new identical laptops. You get the above error on the fourth when creating a new ICA connection from within Program Neighborhood:

1. Change Windows Explorer to show hidden files.
   
2. Search the hard disk for appsrv.ini.
   
3. Right click each instance of the file to verify they are NOT flagged as Read Only.
   

I would concentrate on the {drive}:\Documents and Settings\{username}\Application Data\ICAClient folder.

Comments on why the installs reference different INI files are welcome.