Unable to open .vsd using Visio 2007 Viewer

Hi,

I installed Visio 2007 Professional, but de-installed it as I did not want
to activate it (after the trial period).

Someone pointed me to Visio Viewer which should enable me to view the
vsd-files. I installed Visio 2002/XP. But it turned out that the vsd-file was
incompatible with my 2002/XP installation. So I de-installed Viewer 2002/XP.

Next I installed Visio Viewer 2007. The icon of the vsd-file did not change
(from the unrecognised form to the Visio form). Double clicking the vsd-file
did not start up my viewer. But looking at my software list learns me
'Microsoft Office Visio Viewer 2007' is installed.

What do I need to do to get the viewer working?

Abel
.