diff -upr xlxd/src/cdmriddir.cpp xlxd.uaa/src/cdmriddir.cpp
--- xlxd/src/cdmriddir.cpp	Mon Apr  1 21:20:07 2019
+++ xlxd.uaa/src/cdmriddir.cpp	Sun Apr  7 13:59:36 2019
@@ -152,7 +152,10 @@ bool CDmridDir::IsValidDmrid(const char *sz)
         ok = true;
         for ( size_t i = 0; (i < n) && ok; i++ )
         {
-            ok &= ::isdigit(sz[i]);
+            if ( !::isdigit(sz[i]) )
+            {
+                ok = false;
+            }
         }
     }
     return ok;