diff --git a/CHANGES.md b/CHANGES.md
index ea77607c7..b3d3c180c 100644
--- a/CHANGES.md
+++ b/CHANGES.md
@@ -2,8 +2,10 @@
 
 ## Unreleased - 2020-xx-xx
 * Implement Logger middleware regex exclude pattern [#1723]
+* Print unconfigured `Data<T>` type when attempting extraction. [#1743]
 
 [#1723]: https://github.com/actix/actix-web/pull/1723
+[#1743]: https://github.com/actix/actix-web/pull/1743
 
 ## 3.1.0 - 2020-09-29
 ### Changed
diff --git a/src/data.rs b/src/data.rs
index 6405fd901..01d36569b 100644
--- a/src/data.rs
+++ b/src/data.rs
@@ -1,3 +1,4 @@
+use std::any::type_name;
 use std::ops::Deref;
 use std::sync::Arc;
 
@@ -121,8 +122,9 @@ impl<T: ?Sized + 'static> FromRequest for Data<T> {
         } else {
             log::debug!(
                 "Failed to construct App-level Data extractor. \
-                 Request path: {:?}",
-                req.path()
+                 Request path: {:?} (type: {})",
+                req.path(),
+                type_name::<T>(),
             );
             err(ErrorInternalServerError(
                 "App data is not configured, to configure use App::data()",