diff --git a/tracy/tools/soltracy.cc b/tracy/tools/soltracy.cc
index 94fb13a95269cfa2c9d4483b39e6334a3f0dfcbb..913dab6a705cff9f8485da825821722f9b405bc9 100644
--- a/tracy/tools/soltracy.cc
+++ b/tracy/tools/soltracy.cc
@@ -188,7 +188,7 @@ int main(int argc, char *argv[]) {
     LoadFieldErrs(UserCommandFlag[i].fe_file, true, 1.0, true, 1);
 	
     Ring_GetTwiss(true, 0.0);
-    prtmfile("flat_file_fefile.dat");
+    prtmfile("flat_file_fefile.out");
   }
 
   // read multipole errors from a file; specific for soleil lattice