diff --git a/EXE_GdbModifyCurve.cpp b/EXE_GdbModifyCurve.cpp
index b9fbbf9..028c41d 100644
--- a/EXE_GdbModifyCurve.cpp
+++ b/EXE_GdbModifyCurve.cpp
@@ -126,9 +126,10 @@ ExeOffsetCurveAdv( int nId, double dDist, int nType, int* pnCount)
      // passo alla successiva
       pOffs.Set( OffsCrv.GetLongerCurve()) ;
    }
-   if ( ! bOk)
+   if ( bOk)
+      ExeSetModified() ;
+   else
       nCount = - 1 ;
-   ExeSetModified() ;
   // se richiesto, salvo il comando Lua equivalente
    if ( IsCmdLog()) {
       string sLua ;