iTunes updated on my iPhone 5c to 9.0.2 but now iTunes on my laptop won't connect to my phone
I just got the same error message.  Do you have a Windows system?  Is it Vista Home Premium?  I believe the problem is that iOS 9.0.2 needs iTunes 12.3, but Apple stopped supporting Vista with iTunes 12.3.  When I check for iTunes updates on my computer with Vista it tells me it's the current version.  It is 12.1, which IS the most current version for Windows Vista but the problem is iOS 9.0.2 needs iTunes 12.3.  They could have warned me before updating the iphone that it wouldn't work on the iTunes program that I was using to update the iphone.  Now what?  I have to upgrade Windows just to use itunes with my phone?

UPDATE:  Bingo!  I went to Apple's website and found a page with "older" versions of iTunes.  It's crazy but there was a newer version of iTunes for Vista, even though the iTunes update check tells you 12.1 is the latest. More specifically, I had 12.1.2.7.  I downloaded 12.1.3.6 which still works with Vista and I can connect to my iphone again!  I hope it works for you too!  

So to recap, iTunes 12.1.3.6 will work with Vista AND iOS 9.0.2.  Here's the link for the download. Make sure you choose the right one for your version of Windows and video card (32 bit, 64 bit, or 64 bit for older video cards)
https://discussions.apple.com/docs/DOC-6562#versions