diff --git a/src/noui.cpp b/src/noui.cpp
--- a/src/noui.cpp
+++ b/src/noui.cpp
@@ -45,7 +45,7 @@
     if (!fSecure) {
         LogPrintf("%s: %s\n", strCaption, message);
     }
-    tfm::format(std::cerr, "%s%s\n", strCaption, message);
+    tfm::format(std::cerr, "%s: %s\n", strCaption, message);
     return false;
 }