On his TellingMachine.com blog today Klaus Graefensteiner has a few things you should consider when selecting the right PHP version for your Windows+IIS server.
Questions he suggests will get you started down the right path are things like:
- What version of PHP do I need?
- What CPU architecture is my computer running?
- What http web server is PHP running under?
- What VisualC/C++ Runtime Libraries are the PHP binaries linked against?