If you receive an No input file specified, for an HTTP request made a non-existing .PHP file, then there are no Request Restrictions configured in IIS’ PHP handler settings. Here is how to resolve this no input file specified error in IIS for PHP…

In IIS Manager, open up the Handler Mappings under your server node. Scroll down to Name PHP, or Path *.php, and double click to open up its properties. See the image below.

IIS 10 Module Mappings for *.php handler
IIS 10 Module Mappings for *.php handler

Click Request Restrictions to get the following screen where you can configure and set handler mappings:

IIS 10 Request Restrictions set for *.php, to invoke the handler only for if request is mapped to a file
IIS 10 Request Restrictions set for *.php, to invoke the handler only for if request is mapped to a file

Psst, want to know how to properly configure PHP on IIS?!

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