diff --git a/src/Mod/Fem/Gui/TaskPostBoxes.cpp b/src/Mod/Fem/Gui/TaskPostBoxes.cpp
index 39e71195c1..58c9253eb0 100644
--- a/src/Mod/Fem/Gui/TaskPostBoxes.cpp
+++ b/src/Mod/Fem/Gui/TaskPostBoxes.cpp
@@ -126,7 +126,8 @@ bool TaskDlgPost::reject()
 
 void TaskDlgPost::modifyStandardButtons(QDialogButtonBox* box) {
         
-    box->button(QDialogButtonBox::Apply)->setDefault(true);
+    if(box->button(QDialogButtonBox::Apply))
+        box->button(QDialogButtonBox::Apply)->setDefault(true);
 }