Quick Q for the techies: .vsd
 

I've just been mailed a .vsd file, and it's something neither I, nor obviously my PC have ever come across before.

What is it? and how do I open it?

Assuming it is legit I think that will be a Microsoft Visio file

It's a Visio document - try downloading the MS viewer from here:-

http://www.microsoft.com/downloads/d...displaylang=en

When it opens with the free visio viewer it does so through Internet explorer.