Why "keil" does not able to read "source input files" ?

Why "keil" does not able to read "source input files" ?https://devzone.nordicsemi.com/f/nordic-q-a/16231/why-keil-does-not-able-to-read-source-input-filesI want to make a program for wireless accelerometer with a microcontroller "nrf51822". I prepared the code however I face a problem with the ".h" files such as "nrf_error.h" as the program is not able to get them. I checked the paths however I still haveen-USTelligent Community 13Wed, 07 Sep 2016 11:46:58 GMTRE: Why "keil" does not able to read "source input files" ?https://devzone.nordicsemi.com/thread/61995?ContentTypeID=1Wed, 07 Sep 2016 11:46:58 GMT137ad170-7792-4731-bb38-c0d22fbe4515:56a7d6ec-4104-4c89-a479-c32ea6cc03cebjorn-spockeli<p>You have to add the include paths of the headers that you are using under "Options for Target"-->C/C++ --> Include Paths. See the screenshot below.</p> <p><img src="https://devzone.nordicsemi.com/cfs-file/__key/communityserver-discussions-components-files/4/include_5F00_paths.JPG" alt="image description" /></p><div style="clear:both;"></div>