diff --git a/GeoModelTools/GeoModelFuncSnippets/src/StringUtils.cxx b/GeoModelTools/GeoModelFuncSnippets/src/StringUtils.cxx
index 89b7a0cd649389441f692c972552fe6e9f987ab4..c17fb500cdc2a0b85203ce32d64980eb9ce35c8c 100644
--- a/GeoModelTools/GeoModelFuncSnippets/src/StringUtils.cxx
+++ b/GeoModelTools/GeoModelFuncSnippets/src/StringUtils.cxx
@@ -120,9 +120,10 @@ namespace GeoStrUtils {
             convertToNumber(str.substr(1), number);
             return;
         }
-        if (std::from_chars(str.data(), str.data() + str.size(), number).ec !=  std::errc{}) {
-            THROW_EXCEPTION("convertToNumber() - The string '"<<str<<"'. Contains unallowed chars");
-        }
+	std::istringstream stream(std::string(str.data(), str.data()+str.size()));
+	stream >> number;
+	if (!stream) THROW_EXCEPTION("convertToNumber() - The string '"<<str<<"'. Contains unallowed chars");
+        
     }
     int atoi(std::string_view str) { 
         int result{std::numeric_limits<int>::max()};
@@ -135,4 +136,4 @@ namespace GeoStrUtils {
         convertToNumber(str, result);
         return result;
     }
-}
\ No newline at end of file
+}