Hypergrid Business has an article by Maria Korolov titled: Linden Lab cuts viewer link to OpenSim. This is about a rather subtle change in the Lab’s viewer that creates a not so subtle result.

To use the viewer on a grid other than the Linden grids a small change is made in the desktop icon used to start the viewer. If you right click on the icon and select Properties, you will see a field labeled: Target. It is in the Shortcut tab. The instructions there tell the computer how to start Second Life™.
Knowledgeable computer users will recognize the text as a command line instruction. If you open a command line window you can type in or paste in the text you find there as a command and Windows will start and run the viewer.

