Index: /trunk/FACT++/src/Fits.cc
===================================================================
--- /trunk/FACT++/src/Fits.cc	(revision 12417)
+++ /trunk/FACT++/src/Fits.cc	(revision 12418)
@@ -216,7 +216,12 @@
     }
     if (rename(fFileName.c_str(), corruptName.str().c_str()) != 0)
-        fMess->Error("Could not rename file " + fFileName);
-    else
-        fMess->Message("Renamed file " + fFileName + " to " + corruptName.str());
+    {
+        ostringstream str;
+        str << "rename() failed for '" << fFileName << "': " << strerror(errno) << " [errno=" << errno << "]";
+        fMess->Error(str);
+        return;
+    }
+
+    fMess->Message("Renamed file " + fFileName + " to " + corruptName.str());
 
 }