diff --git a/plexus-compilers/plexus-compiler-csharp/src/main/java/org/codehaus/plexus/compiler/csharp/CSharpCompiler.java b/plexus-compilers/plexus-compiler-csharp/src/main/java/org/codehaus/plexus/compiler/csharp/CSharpCompiler.java
index e223ff68..2fe06177 100644
--- a/plexus-compilers/plexus-compiler-csharp/src/main/java/org/codehaus/plexus/compiler/csharp/CSharpCompiler.java
+++ b/plexus-compilers/plexus-compiler-csharp/src/main/java/org/codehaus/plexus/compiler/csharp/CSharpCompiler.java
@@ -759,7 +759,7 @@ protected static Set<String> getSourceFilesForSourceRoot(CompilerConfiguration c
 
         if (excludes != null && !excludes.isEmpty()) {
             String[] exclStrs = excludes.toArray(new String[excludes.size()]);
-            scanner.setIncludes(exclStrs);
+            scanner.setExcludes(exclStrs);
         }
 
         scanner.scan();