diff --git a/src/OSSupport/GZipFile.cpp b/src/OSSupport/GZipFile.cpp
index 7a8433f4f..22d887783 100644
--- a/src/OSSupport/GZipFile.cpp
+++ b/src/OSSupport/GZipFile.cpp
@@ -11,7 +11,7 @@
 
 
 cGZipFile::cGZipFile(void) :
-	m_File(NULL)
+	m_File(NULL), m_Mode(fmRead)
 {
 }