diff --git a/src/slic3r/GUI/format.hpp b/src/slic3r/GUI/format.hpp
index 5cb3aed4c..bc6fe7b1b 100644
--- a/src/slic3r/GUI/format.hpp
+++ b/src/slic3r/GUI/format.hpp
@@ -29,7 +29,7 @@ inline wxString format_wxstr(const wxString& fmt, TArgs&&... args) {
 }
 template<typename... TArgs>
 inline std::string format(const wxString& fmt, TArgs&&... args) {
-	return format(fmt.ToUTF8().data(), std::forward<TArgs>(args)...);
+    return Slic3r::format(fmt.ToUTF8().data(), std::forward<TArgs>(args)...);
 }
 
 } // namespace GUI
diff --git a/src/slic3r/Utils/Http.cpp b/src/slic3r/Utils/Http.cpp
index 1f1b6d306..a16aac5b5 100644
--- a/src/slic3r/Utils/Http.cpp
+++ b/src/slic3r/Utils/Http.cpp
@@ -74,11 +74,11 @@ struct CurlGlobalInit
                                "PrusaSlicer will be unable to establish secure "
                                "network connections.");
             else
-                message = Slic3r::format(
+                message = Slic3r::GUI::format(
 					_L("PrusaSlicer detected system SSL certificate store in: %1%"),
                     bundle);
 
-            message += "\n" + Slic3r::format(
+            message += "\n" + Slic3r::GUI::format(
 				_L("To specify the system certificate store manually, please "
                    "set the %1% environment variable to the correct CA bundle "
                    "and restart the application."),