diff --git a/src/ce_main.lfm b/src/ce_main.lfm
index 91a5ef0d..bbf9b730 100644
--- a/src/ce_main.lfm
+++ b/src/ce_main.lfm
@@ -6519,6 +6519,7 @@ object CEMainForm: TCEMainForm
     }
   end
   object ApplicationProperties1: TApplicationProperties
+    OnActivate = ApplicationProperties1Activate
     OnException = ApplicationProperties1Exception
     left = 96
     top = 1
diff --git a/src/ce_main.pas b/src/ce_main.pas
index 1403ca22..820ac373 100644
--- a/src/ce_main.pas
+++ b/src/ce_main.pas
@@ -286,6 +286,7 @@ type
     procedure actProjSaveGroupExecute(Sender: TObject);
     procedure actProjSelUngroupedExecute(Sender: TObject);
     procedure actSetRunnableSwExecute(Sender: TObject);
+    procedure ApplicationProperties1Activate(Sender: TObject);
     procedure FormClose(Sender: TObject; var CloseAction: TCloseAction);
     procedure updateDocumentBasedAction(sender: TObject);
     procedure updateProjectBasedAction(sender: TObject);
@@ -2603,6 +2604,12 @@ begin
   form.Free;
 end;
 
+procedure TCEMainForm.ApplicationProperties1Activate(Sender: TObject);
+begin
+  if fDoc.isNotNil then
+    fDoc.checkFileDate;
+end;
+
 function TCEMainForm.compileRunnable(unittest: boolean = false): boolean;
 var
   i: integer;