Can anyone explain if it is possible to have a web server for all of these technologies:
ColdFusion, PHP, MS SQL Server, MySQL
I have a web developer insisting that they require all of the above however it doesn't quite make sense to me.
Any help or clarification is appreciated.
It's possible, but MS SQL being a Windows only product, you'll need a Windows server, preferably one from the Server family (Windows Server 2003 or 2008). PHP and mySQL can run happily on Windows, I've got them both running on the Windows 7 machine I'm writing this on.
I don't know whether a hosting provider will run all these things on the same server in a standard (cheap) package - you may have to have one tailor-made. But that depends entirely on your situation, of course.
As to whether this makes sense, though - I don't know. Is this a new product being developed? Then it sounds very strange to need two different database platforms, and two entirely different web development environments. If it's to integrate a number of existing products, it may make sense.