diff --git a/CSharp.gitignore b/CSharp.gitignore
index bdc3535f..c0fa8c99 100644
--- a/CSharp.gitignore
+++ b/CSharp.gitignore
@@ -106,3 +106,6 @@ Generated_Code #added for RIA/Silverlight projects
 _UpgradeReport_Files/
 Backup*/
 UpgradeLog*.XML
+
+# Windows System Files
+Thumbs.db
\ No newline at end of file