diff --git a/IPhreeqc.vcproj b/IPhreeqc.vcproj
index 57651ed2..b9e6e717 100644
--- a/IPhreeqc.vcproj
+++ b/IPhreeqc.vcproj
@@ -1111,10 +1111,6 @@
 				RelativePath=".\src\phreeqcpp\phreeqc\input.h"
 				>
 			</File>
-			<File
-				RelativePath=".\src\IPHRQ_io.h"
-				>
-			</File>
 			<File
 				RelativePath=".\src\phreeqcpp\ISolution.h"
 				>