diff --git a/src/ce_dfmt.pas b/src/ce_dfmt.pas
index 1abb848c..27b19dc6 100644
--- a/src/ce_dfmt.pas
+++ b/src/ce_dfmt.pas
@@ -253,6 +253,8 @@ var
 begin
   if not assigned(fDoc) then
     exit;
+  if not exeInSysPath('dfmt') then
+    exit;
 
   fBackup.Assign(fDoc.Lines);
   prc := TProcess.create(nil);