Geoff A code example worked fairly well on my machine.
My dev machine has four instances installed:
2008 standard (default).
2005 Express.
2008R2 Developer.
2012 Developer.
The above query seems to have missed my 2005 SQL Express instance, which i clearly see did not place a key in the SOFTWARE\Microsoft\Microsoft SQL Server\InstalledInstances folder of the registry.
do you think it's caused by 2005 not putting a key there, or that Express instances don't put a key there?
i tried Netstat -a -b on a command line, and i see multiple sqlserver.exe's running and listing to various ports, but can't map them directly to their instances.
Lowell