--- a/src/testdir/test_vim9_script.vim
+++ b/src/testdir/test_vim9_script.vim
@@ -5002,7 +5002,7 @@ def Test_invalid_type_in_for()
     enddef
     defcompile
   END
-  v9.CheckSourceFailure(lines, 'E1010: Type not recognized: x in range(10)', 1)
+  v9.CheckSourceFailure(lines, 'E1010: Type not recognized: x', 1)
 enddef
 
 " Test for using a line break between the variable name and the type in a for
@@ -5083,6 +5083,21 @@ def Test_null_values()
   v9.CheckSourceDefAndScriptSuccess(lines)
 enddef
 
+" Test for using an unknown type in a typecast
+def Test_unknown_type_in_typecast()
+  var lines =<< trim END
+    vim9script
+    var a = <MyType>b
+  END
+  v9.CheckSourceFailure(lines, 'E1010: Type not recognized: MyType', 2)
+
+  lines =<< trim END
+    vim9script
+    var Fn = <funcx(number, number): number>b
+  END
+  v9.CheckSourceFailure(lines, 'E1010: Type not recognized: funcx(number, number): number', 2)
+enddef
+
 " Keep this last, it messes up highlighting.
 def Test_substitute_cmd()
   new

--- a/src/testdir/test_vim9_typealias.vim
+++ b/src/testdir/test_vim9_typealias.vim
@@ -363,7 +363,7 @@ def Test_typealias_import()
 
     var myNum: A.SomeType = 10
   END
-  v9.CheckScriptFailure(lines, 'E1010: Type not recognized: A.SomeType = 10', 4)
+  v9.CheckScriptFailure(lines, 'E1010: Type not recognized: A.SomeType', 4)
 
   # Use a type alias that is not exported
   lines =<< trim END

--- a/src/version.c
+++ b/src/version.c
@@ -705,6 +705,8 @@ static char *(features[]) =
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    400,
+/**/
     399,
 /**/
     398,

--- a/src/vim9type.c
+++ b/src/vim9type.c
@@ -1466,7 +1466,14 @@ parse_type_user_defined(
     }
 
     if (give_error && (did_emsg == did_emsg_before))
+    {
+	char_u	*p = skip_type(*arg, FALSE);
+	char	cc = *p;
+
+	*p = NUL;
 	semsg(_(e_type_not_recognized_str), *arg);
+	*p = cc;
+    }
 
     return NULL;
 }