diff --git a/.github/workflows/main.yml b/.github/workflows/main.yml
index b68d295..edf208a 100644
--- a/.github/workflows/main.yml
+++ b/.github/workflows/main.yml
@@ -51,7 +51,9 @@ jobs:
         shell: bash -l {0}
         run: |
           pytest -v \
+            --durations=10 \
             --cov=micropip \
+            --maxfail=5 \
             --dist-dir=./dist/ \
             --runner=${{ matrix.test-config.runner }} \
             --rt ${{ matrix.test-config.runtime }}
diff --git a/micropip/_compat/__init__.py b/micropip/_compat/__init__.py
index 3934238..445e63d 100644
--- a/micropip/_compat/__init__.py
+++ b/micropip/_compat/__init__.py
@@ -34,6 +34,8 @@
 
 to_js = compatibility_layer.to_js
 
+HttpStatusError = compatibility_layer.HttpStatusError
+
 
 __all__ = [
     "REPODATA_INFO",
@@ -45,4 +47,5 @@
     "loadPackage",
     "get_dynlibs",
     "to_js",
+    "HttpStatusError",
 ]
diff --git a/micropip/_compat/_compat_in_pyodide.py b/micropip/_compat/_compat_in_pyodide.py
index 671fc44..58fb8f1 100644
--- a/micropip/_compat/_compat_in_pyodide.py
+++ b/micropip/_compat/_compat_in_pyodide.py
@@ -5,9 +5,21 @@
 if TYPE_CHECKING:
     pass
 
+import pyodide
+from packaging.version import parse
 from pyodide._package_loader import get_dynlibs
 from pyodide.ffi import IN_BROWSER, to_js
-from pyodide.http import pyfetch
+
+if parse(pyodide.__version__) > parse("0.27"):
+    from pyodide.http import HttpStatusError, pyfetch
+else:
+
+    class HttpStatusError(Exception):  # type: ignore [no-redef]
+        """we just want this to be defined, it is never going to be raised"""
+
+        pass
+
+    from pyodide.http import pyfetch
 
 from .compatibility_layer import CompatibilityLayer
 
@@ -28,6 +40,15 @@
 
 
 class CompatibilityInPyodide(CompatibilityLayer):
+    class HttpStatusError(Exception):
+        status_code: int
+        message: str
+
+        def __init__(self, status_code: int, message: str):
+            self.status_code = status_code
+            self.message = message
+            super().__init__(message)
+
     @staticmethod
     def repodata_info() -> dict[str, str]:
         return REPODATA_INFO
@@ -50,7 +71,11 @@ async def fetch_bytes(url: str, kwargs: dict[str, str]) -> bytes:
     async def fetch_string_and_headers(
         url: str, kwargs: dict[str, str]
     ) -> tuple[str, dict[str, str]]:
-        response = await pyfetch(url, **kwargs)
+        try:
+            response = await pyfetch(url, **kwargs)
+            response.raise_for_status()
+        except HttpStatusError as e:
+            raise CompatibilityInPyodide.HttpStatusError(e.status, str(e)) from e
 
         content = await response.string()
         headers: dict[str, str] = response.headers
diff --git a/micropip/_compat/_compat_not_in_pyodide.py b/micropip/_compat/_compat_not_in_pyodide.py
index 5fb3cec..96cc53b 100644
--- a/micropip/_compat/_compat_not_in_pyodide.py
+++ b/micropip/_compat/_compat_not_in_pyodide.py
@@ -1,6 +1,7 @@
 import re
 from pathlib import Path
 from typing import IO, TYPE_CHECKING, Any
+from urllib.error import HTTPError
 from urllib.request import Request, urlopen
 from urllib.response import addinfourl
 
@@ -15,6 +16,15 @@ class CompatibilityNotInPyodide(CompatibilityLayer):
     # Vendored from packaging
     _canonicalize_regex = re.compile(r"[-_.]+")
 
+    class HttpStatusError(Exception):
+        status_code: int
+        message: str
+
+        def __init__(self, status_code: int, message: str):
+            self.status_code = status_code
+            self.message = message
+            super().__init__(message)
+
     class loadedPackages(CompatibilityLayer.loadedPackages):
         @staticmethod
         def to_py():
@@ -40,7 +50,11 @@ async def fetch_bytes(url: str, kwargs: dict[str, Any]) -> bytes:
     async def fetch_string_and_headers(
         url: str, kwargs: dict[str, Any]
     ) -> tuple[str, dict[str, str]]:
-        response = CompatibilityNotInPyodide._fetch(url, kwargs=kwargs)
+        try:
+            response = CompatibilityNotInPyodide._fetch(url, kwargs=kwargs)
+        except HTTPError as e:
+            raise CompatibilityNotInPyodide.HttpStatusError(e.code, str(e)) from e
+
         headers = {k.lower(): v for k, v in response.headers.items()}
         return response.read().decode(), headers
 
diff --git a/micropip/_compat/compatibility_layer.py b/micropip/_compat/compatibility_layer.py
index 07a0c37..b6c6c86 100644
--- a/micropip/_compat/compatibility_layer.py
+++ b/micropip/_compat/compatibility_layer.py
@@ -13,6 +13,14 @@ class CompatibilityLayer(ABC):
     All of the following methods / properties must be implemented for use both inside and outside of pyodide.
     """
 
+    class HttpStatusError(ABC, Exception):
+        status_code: int
+        message: str
+
+        @abstractmethod
+        def __init__(self, status_code: int, message: str):
+            pass
+
     class loadedPackages(ABC):
         @staticmethod
         @abstractmethod
diff --git a/micropip/package_index.py b/micropip/package_index.py
index 2772b7b..f3d43e3 100644
--- a/micropip/package_index.py
+++ b/micropip/package_index.py
@@ -10,7 +10,7 @@
 from packaging.utils import InvalidWheelFilename
 from packaging.version import InvalidVersion, Version
 
-from ._compat import fetch_string_and_headers
+from ._compat import HttpStatusError, fetch_string_and_headers
 from ._utils import is_package_compatible, parse_version
 from .externals.mousebender.simple import from_project_details_html
 from .wheelinfo import WheelInfo
@@ -276,11 +276,33 @@ async def query_package(
 
         try:
             metadata, headers = await fetch_string_and_headers(url, _fetch_kwargs)
+        except HttpStatusError as e:
+            if e.status_code == 404:
+                continue
+            raise
         except OSError:
-            continue
+            # temporary pyodide compatibility.
+            # pypi now set proper CORS on 404 (https://github.com/pypi/warehouse/pull/16339),
+            # but stable pyodide (<0.27) does not yet have proper HttpStatusError exception
+            # so when: on pyodide and 0.26.x we ignore OSError. Once we drop support for 0.26
+            # all this OSError except clause should just be gone.
+            try:
+                import pyodide
+                from packaging.version import parse
+
+                if parse(pyodide.__version__) > parse("0.27"):
+                    # reraise on more recent pyodide.
+                    raise
+                continue
+            except ImportError:
+                # not in pyodide.
+                raise
 
         content_type = headers.get("content-type", "").lower()
-        parser = _select_parser(content_type, name)
+        try:
+            parser = _select_parser(content_type, name)
+        except ValueError as e:
+            raise ValueError(f"Error trying to decode url: {url}") from e
         return parser(metadata)
     else:
         raise ValueError(
diff --git a/tests/conftest.py b/tests/conftest.py
index c53d723..6f597be 100644
--- a/tests/conftest.py
+++ b/tests/conftest.py
@@ -72,6 +72,9 @@ def selenium_standalone_micropip(selenium_standalone, wheel_path):
     if not wheel_files:
         pytest.exit("No wheel files found in wheel/ directory")
 
+    # Change  default timeout to 30s instead of 10min
+    selenium_standalone.driver.implicitly_wait(11)
+
     wheel_file = wheel_files[0]
     with spawn_web_server(wheel_dir) as server:
         server_hostname, server_port, _ = server
@@ -340,6 +343,7 @@ def mock_fetch(monkeypatch, mock_importlib):
 def _mock_package_index_gen(
     httpserver,
     pkgs=("black", "pytest", "numpy", "pytz", "snowballstemmer"),
+    pkgs_not_found=(),
     content_type="application/json",
     suffix="_json.json.gz",
 ):
@@ -355,6 +359,10 @@ def _mock_package_index_gen(
             content_type=content_type,
             headers={"Access-Control-Allow-Origin": "*"},
         )
+    for pkg in pkgs_not_found:
+        httpserver.expect_request(f"/{base}/{pkg}/").respond_with_data(
+            "Not found", status=404, content_type="text/plain"
+        )
 
     index_url = httpserver.url_for(base)
 
diff --git a/tests/test_compat.py b/tests/test_compat.py
new file mode 100644
index 0000000..492831a
--- /dev/null
+++ b/tests/test_compat.py
@@ -0,0 +1,37 @@
+"""
+test that function in compati behave the same
+
+"""
+
+import pytest
+from pytest_pyodide import run_in_pyodide
+
+
+@pytest.mark.driver_timeout(10)
+def test_404(selenium_standalone_micropip, httpserver, request):
+    selenium_standalone_micropip.set_script_timeout(11)
+
+    @run_in_pyodide(packages=["micropip", "packaging"])
+    async def _inner_test_404_raise(selenium, url):
+        import pyodide
+        import pytest
+        from packaging.version import parse
+
+        from micropip._compat import HttpStatusError, fetch_string_and_headers
+
+        if parse(pyodide.__version__) > parse("0.27"):
+            ExpectedErrorClass = HttpStatusError
+        else:
+            ExpectedErrorClass = OSError
+
+        with pytest.raises(ExpectedErrorClass):
+            await fetch_string_and_headers(url, {})
+
+    httpserver.expect_request("/404").respond_with_data(
+        "Not found",
+        status=404,
+        content_type="text/plain",
+        headers={"Access-Control-Allow-Origin": "*"},
+    )
+    url_404 = httpserver.url_for("/404")
+    _inner_test_404_raise(selenium_standalone_micropip, url_404)
diff --git a/tests/test_package_index.py b/tests/test_package_index.py
index 9097877..5552f60 100644
--- a/tests/test_package_index.py
+++ b/tests/test_package_index.py
@@ -135,8 +135,8 @@ def test_contain_placeholder():
 )
 async def test_query_package(mock_fixture, pkg1, pkg2, request):
     gen_mock_server = request.getfixturevalue(mock_fixture)
-    pkg1_index_url = gen_mock_server(pkgs=[pkg1])
-    pkg2_index_url = gen_mock_server(pkgs=[pkg2])
+    pkg1_index_url = gen_mock_server(pkgs=[pkg1], pkgs_not_found=[pkg2])
+    pkg2_index_url = gen_mock_server(pkgs=[pkg2], pkgs_not_found=[pkg1])
 
     for _index_urls in (
         pkg1_index_url,