diff --git a/resources/js/components/assets/Browser/Browser.vue b/resources/js/components/assets/Browser/Browser.vue
index 40eb5ea7107..0ba7ae383b6 100644
--- a/resources/js/components/assets/Browser/Browser.vue
+++ b/resources/js/components/assets/Browser/Browser.vue
@@ -740,10 +740,7 @@ export default {
         },
 
         existingUploadSelected(upload) {
-            const path = `${this.folder.path}/${upload.basename}`.replace(/^\/+/, '');
-            const id = `${this.container.id}::${path}`;
-
-            this.selectedAssets.push(id);
+            this.selectedAssets.push(upload.existingId);
             this.$emit('selections-updated', this.selectedAssets);
         },
 
diff --git a/resources/js/components/assets/Uploader.vue b/resources/js/components/assets/Uploader.vue
index 6ec9948155d..a324eb99684 100644
--- a/resources/js/components/assets/Uploader.vue
+++ b/resources/js/components/assets/Uploader.vue
@@ -307,6 +307,7 @@ export default {
 
             upload.errorMessage = msg;
             upload.errorStatus = status;
+            upload.existingId = response?.existing;
             this.$emit('error', upload, this.uploads);
             this.processUploadQueue();
         },
diff --git a/resources/js/components/fieldtypes/assets/AssetsFieldtype.vue b/resources/js/components/fieldtypes/assets/AssetsFieldtype.vue
index c07eb1f1ccc..3a63bba2cc1 100644
--- a/resources/js/components/fieldtypes/assets/AssetsFieldtype.vue
+++ b/resources/js/components/fieldtypes/assets/AssetsFieldtype.vue
@@ -656,8 +656,7 @@ export default {
         },
 
         uploadSelected(upload) {
-            const path = `${this.folder}/${upload.basename}`.replace(/^\/+/, '');
-            const id = `${this.container.id}::${path}`;
+            const id = upload.existingId;
 
             this.uploads.splice(this.uploads.indexOf(upload), 1);
 
diff --git a/resources/js/tests/components/fieldtypes/AssetsFieldtype.test.js b/resources/js/tests/components/fieldtypes/AssetsFieldtype.test.js
index ff68cff46fa..4cb805f3786 100644
--- a/resources/js/tests/components/fieldtypes/AssetsFieldtype.test.js
+++ b/resources/js/tests/components/fieldtypes/AssetsFieldtype.test.js
@@ -33,22 +33,13 @@ const makeField = ({ axiosPost = vi.fn(() => Promise.resolve({ data: [] })), pro
     });
 };
 
-test('selecting the existing file references it by the container id', () => {
-    const post = vi.fn(() => Promise.resolve({ data: [] }));
-    const field = makeField({ axiosPost: post });
-
-    field.vm.uploadSelected({ basename: 'user.png' });
-
-    expect(post).toHaveBeenCalledWith('assets-fieldtype', { assets: ['main::user.png'] });
-});
-
-test('the existing file id includes the configured folder', () => {
+test('selecting the existing file references the asset the server reported', () => {
     const post = vi.fn(() => Promise.resolve({ data: [] }));
     const field = makeField({ axiosPost: post, props: { config: { folder: 'sub' } } });
 
-    field.vm.uploadSelected({ basename: 'user.png' });
+    field.vm.uploadSelected({ basename: 'My File.PNG', existingId: 'main::sub/my-file.png' });
 
-    expect(post).toHaveBeenCalledWith('assets-fieldtype', { assets: ['main::sub/user.png'] });
+    expect(post).toHaveBeenCalledWith('assets-fieldtype', { assets: ['main::sub/my-file.png'] });
 });
 
 test('loading assets for a new value does not emit an update when the ids are unchanged', async () => {
diff --git a/src/Http/Controllers/CP/Assets/AssetsController.php b/src/Http/Controllers/CP/Assets/AssetsController.php
index 8aeb7585c95..3b7eb812b1f 100644
--- a/src/Http/Controllers/CP/Assets/AssetsController.php
+++ b/src/Http/Controllers/CP/Assets/AssetsController.php
@@ -124,7 +124,12 @@ public function store(Request $request)
             try {
                 $validator->validate();
             } catch (ValidationException $e) {
-                throw $e->status(409);
+                // The sanitized path can differ from the uploaded filename, so tell the uploader which asset exists.
+                return response()->json([
+                    'message' => __('The given data was invalid.'),
+                    'errors' => $e->errors(),
+                    'existing' => $container->asset($path)->id(),
+                ], 409);
             }
         }
 
diff --git a/tests/Feature/Assets/StoreAssetTest.php b/tests/Feature/Assets/StoreAssetTest.php
index 96a4e79b0a6..4d389b897e1 100644
--- a/tests/Feature/Assets/StoreAssetTest.php
+++ b/tests/Feature/Assets/StoreAssetTest.php
@@ -134,7 +134,8 @@ public function it_doesnt_upload_when_file_exists_with_different_casing()
                 'file' => UploadedFile::fake()->image('tEsT.jpg'),
             ])
             ->assertStatus(409)
-            ->assertInvalid(['path' => 'A file already exists with this name.']);
+            ->assertInvalid(['path' => 'A file already exists with this name.'])
+            ->assertJson(['message' => 'The given data was invalid.', 'existing' => 'test_container::path/to/test.jpg']);
     }
 
     #[Test]