diff --git a/Code/Mantid/Framework/Kernel/src/DateValidator.cpp b/Code/Mantid/Framework/Kernel/src/DateValidator.cpp
index db5f6fec763f..4e8696761ecf 100644
--- a/Code/Mantid/Framework/Kernel/src/DateValidator.cpp
+++ b/Code/Mantid/Framework/Kernel/src/DateValidator.cpp
@@ -26,7 +26,7 @@ namespace Kernel
       // Zero it out
       timeinfo.tm_sec = 0; timeinfo.tm_min = 0; timeinfo.tm_hour = 0;
       timeinfo.tm_mday = 0; timeinfo.tm_mon = 0; timeinfo.tm_year = 0;
-      timeinfo.tm_isdst = -1;
+      timeinfo.tm_wday = 0; timeinfo.tm_isdst = -1;
 
       std::basic_string<char>::size_type index, off = 0;
       int day, month, year;