diff --git a/src/validation.rs b/src/validation.rs
index aadf8f8..939eeda 100644
--- a/src/validation.rs
+++ b/src/validation.rs
@@ -88,6 +88,11 @@ impl FileValidator {
             "application/vnd.openxmlformats-officedocument.wordprocessingml.document" | // .docx
             "application/vnd.openxmlformats-officedocument.presentationml.presentation" | // .pptx
             "application/vnd.ms-powerpoint" |                                    // .ppt
+            // Some tooling (e.g. python-docx) emits OOXML zips with non-standard
+            // entry ordering, so `infer` reports `application/zip` instead of the
+            // specific OOXML mime. Pair this with the extension check in
+            // `is_compatible_type` to still reject random zips.
+            "application/zip" |
             "application/octet-stream" // Generic binary
         )
     }
@@ -96,6 +101,9 @@ impl FileValidator {
         detected == extension
             || (detected == "application/octet-stream" && self.is_supported_mime(extension))
             || (extension == "application/octet-stream" && self.is_supported_mime(detected))
+            // OOXML files are zips; trust the extension when content-detection only
+            // sees the underlying zip container.
+            || (detected == "application/zip" && self.is_supported_mime(extension))
     }
 }
 
diff --git a/tests/fixtures/test_document_rels_first.docx b/tests/fixtures/test_document_rels_first.docx
new file mode 100644
index 0000000..aa61b8b
Binary files /dev/null and b/tests/fixtures/test_document_rels_first.docx differ
diff --git a/tests/integration_tests.rs b/tests/integration_tests.rs
index e375b17..b2093fd 100644
--- a/tests/integration_tests.rs
+++ b/tests/integration_tests.rs
@@ -137,6 +137,40 @@ async fn test_successful_docx_conversion() {
     assert_eq!(&pdf_content[0..4], b"%PDF");
 }
 
+// docx files generated by python-docx (and other tooling) put _rels/.rels before
+// [Content_Types].xml inside the zip, so `infer` falls back to application/zip rather
+// than the OOXML mime. Validator must still accept these as long as the extension matches.
+#[tokio::test]
+async fn test_docx_with_nonstandard_zip_ordering() {
+    ensure_server_running();
+    wait_for_server_ready().await;
+    let client = reqwest::Client::new();
+
+    let file_path = get_test_file_path("test_document_rels_first.docx");
+    let file_content = fs::read(&file_path).expect("Failed to read fixture");
+
+    let form = multipart::Form::new()
+        .part(
+            "file_content",
+            multipart::Part::bytes(file_content)
+                .mime_str("application/octet-stream")
+                .unwrap()
+                .file_name("test_document_rels_first.docx"),
+        )
+        .text("file_name", "test_document_rels_first.docx");
+
+    let response = client
+        .post(format!("{}/convert2/pdf", TEST_SERVER_URL))
+        .multipart(form)
+        .send()
+        .await
+        .expect("Failed to make conversion request");
+
+    assert_eq!(response.status(), 200);
+    let pdf_content = response.bytes().await.expect("Failed to read PDF response");
+    assert_eq!(&pdf_content[0..4], b"%PDF");
+}
+
 #[tokio::test]
 async fn test_successful_xlsx_conversion() {
     ensure_server_running();