Update README.md

Author: spectralcode

README.md

@@ -5,7 +5,7 @@ FDMLControl enables the control of the [Optores](https://www.optores.com/) FDML
 <!-- this is a
 comment - with hyphen -->
 
-![screenshot](images/FDMLConrol_screenshotWin10.PNG)
+![screenshot](images/FDMLConrol_screenshotWin10.png)
 
 Features
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