diff --git a/aqt/archives.py b/aqt/archives.py
index 480f5bf..64730c9 100644
--- a/aqt/archives.py
+++ b/aqt/archives.py
@@ -98,19 +98,16 @@ class QtArchives:
         else:
             for m in modules if modules is not None else []:
                 self.mod_list.append(
-                    "qt.qt{0}.{0}{1}{2}.{3}.{4}".format(
+                    "qt.qt{0}.{1}.{2}.{3}".format(
                         self.version.major,
-                        self.version.minor,
-                        self.version.patch,
+                        self._version_str(),
                         m,
                         arch,
                     )
                 )
                 self.mod_list.append(
-                    "qt.{0}{1}{2}.{3}.{4}".format(
-                        self.version.major,
-                        self.version.minor,
-                        self.version.patch,
+                    "qt.{0}.{1}.{2}".format(
+                        self._version_str(),
                         m,
                         arch,
                     )
@@ -120,6 +117,11 @@ class QtArchives:
         if not all_archives:
             self.archives = list(filter(lambda a: a.name in subarchives, self.archives))
 
+    def _version_str(self) -> str:
+        return ("{0.major}{0.minor}" if self.version == Version("5.9.0") else "{0.major}{0.minor}{0.patch}").format(
+            self.version
+        )
+
     def _get_archives(self):
         # Get packages index
         if self.arch == "wasm_32":
@@ -128,29 +130,25 @@ class QtArchives:
             arch_ext = "{}".format(self.arch[7:])
         else:
             arch_ext = ""
-        archive_path = "{0}{1}{2}/qt{3}_{3}{4}{5}{6}/".format(
+        archive_path = "{0}{1}/{2}/qt{3}_{4}{5}/".format(
             self.os_name,
-            "_x86/" if self.os_name == "windows" else "_x64/",
+            "_x86" if self.os_name == "windows" else "_x64",
             self.target,
             self.version.major,
-            self.version.minor,
-            self.version.patch,
+            self._version_str(),
             arch_ext,
         )
         update_xml_url = "{0}{1}Updates.xml".format(self.base, archive_path)
         archive_url = "{0}{1}".format(self.base, archive_path)
         target_packages = []
         target_packages.append(
-            "qt.qt{0}.{0}{1}{2}.{3}".format(
+            "qt.qt{0}.{1}.{2}".format(
                 self.version.major,
-                self.version.minor,
-                self.version.patch,
+                self._version_str(),
                 self.arch,
             )
         )
-        target_packages.append(
-            "qt.{0}{1}{2}.{3}".format(self.version.major, self.version.minor, self.version.patch, self.arch)
-        )
+        target_packages.append("qt.{0}.{1}".format(self._version_str(), self.arch))
         target_packages.extend(self.mod_list)
         self._download_update_xml(update_xml_url)
         self._parse_update_xml(archive_url, target_packages)
diff --git a/aqt/updater.py b/aqt/updater.py
index e8ee446..ca75402 100644
--- a/aqt/updater.py
+++ b/aqt/updater.py
@@ -258,6 +258,7 @@ class Updater:
         arch = target.arch
         version = Version(target.version)
         os_name = target.os_name
+        version_dir = "5.9" if version == Version("5.9.0") else target.version
         if arch is None:
             arch_dir = ""
         elif arch.startswith("win64_mingw"):
@@ -276,9 +277,9 @@ class Updater:
         else:
             arch_dir = arch
         try:
-            prefix = pathlib.Path(base_dir) / target.version / arch_dir
+            prefix = pathlib.Path(base_dir) / version_dir / arch_dir
             updater = Updater(prefix, logger)
-            updater.set_license(base_dir, target.version, arch_dir)
+            updater.set_license(base_dir, version_dir, arch_dir)
             if target.arch not in [
                 "ios",
                 "android",
@@ -288,7 +289,7 @@ class Updater:
                 "android_x86",
                 "android_armv7",
             ]:  # desktop version
-                updater.make_qtconf(base_dir, target.version, arch_dir)
+                updater.make_qtconf(base_dir, version_dir, arch_dir)
                 updater.patch_qmake()
                 if target.os_name == "linux":
                     updater.patch_pkgconfig("/home/qt/work/install", target.os_name)
@@ -297,14 +298,14 @@ class Updater:
                     updater.patch_pkgconfig("/Users/qt/work/install", target.os_name)
                     updater.patch_libtool("/Users/qt/work/install/lib", target.os_name)
                 elif target.os_name == "windows":
-                    updater.make_qtenv2(base_dir, target.version, arch_dir)
-                if Version(target.version) < Version("5.14.0"):
+                    updater.make_qtenv2(base_dir, version_dir, arch_dir)
+                if version < Version("5.14.0"):
                     updater.patch_qtcore(target)
-            elif Version(target.version) in SimpleSpec(">=5.0,<6.0"):
+            elif version in SimpleSpec(">=5.0,<6.0"):
                 updater.patch_qmake()
             else:  # qt6 non-desktop
-                updater.patch_qmake_script(base_dir, target.version, target.os_name)
-                updater.patch_target_qt_conf(base_dir, target.version, arch_dir, target.os_name)
+                updater.patch_qmake_script(base_dir, version_dir, target.os_name)
+                updater.patch_target_qt_conf(base_dir, version_dir, arch_dir, target.os_name)
         except IOError as e:
             raise e
 
diff --git a/ci/generate_azure_pipelines_matrices.py b/ci/generate_azure_pipelines_matrices.py
index fd07338..4651e18 100644
--- a/ci/generate_azure_pipelines_matrices.py
+++ b/ci/generate_azure_pipelines_matrices.py
@@ -44,6 +44,14 @@ class BuildJob:
         self.spec = spec
         self.output_dir = output_dir
 
+    def qt_bindir(self, *, sep='/') -> str:
+        out_dir = f"$(Build.BinariesDirectory){sep}Qt" if not self.output_dir else self.output_dir
+        version_dir = "5.9" if self.qt_version == "5.9.0" else self.qt_version
+        return f"{out_dir}{sep}{version_dir}{sep}{self.archdir}{sep}bin"
+
+    def win_qt_bindir(self) -> str:
+        return self.qt_bindir(sep='\\')
+
 
 class PlatformBuildJobs:
     def __init__(self, platform, build_jobs):
@@ -130,6 +138,16 @@ windows_build_jobs.extend(
             module="qtcharts qtnetworkauth",
             mirror=random.choice(MIRRORS),
         ),
+        BuildJob(
+            "install-qt",
+            "5.9.0",
+            "windows",
+            "desktop",
+            "win64_msvc2017_64",
+            "msvc2017_64",
+            module="qtcharts qtnetworkauth",
+            mirror=random.choice(MIRRORS),
+        ),
     ]
 )
 
@@ -281,24 +299,8 @@ for platform_build_job in all_platform_build_jobs:
                 ("HAS_EXTENSIONS", build_job.list_options.get("HAS_EXTENSIONS", "False")),
                 ("USE_EXTENSION", build_job.list_options.get("USE_EXTENSION", "None")),
                 ("OUTPUT_DIR", build_job.output_dir if build_job.output_dir else ""),
-                (
-                    "QT_BINDIR",
-                    "{0}/{1.qt_version}/{1.archdir}/bin".format(
-                        "$(Build.BinariesDirectory)/Qt"
-                        if not build_job.output_dir
-                        else build_job.output_dir,
-                        build_job,
-                    ),
-                ),
-                (
-                    "WIN_QT_BINDIR",
-                    "{0}\\{1.qt_version}\\{1.archdir}\\bin".format(
-                        "$(Build.BinariesDirectory)\\Qt"
-                        if not build_job.output_dir
-                        else build_job.output_dir,
-                        build_job,
-                    ),
-                ),
+                ("QT_BINDIR", build_job.qt_bindir()),
+                ("WIN_QT_BINDIR", build_job.win_qt_bindir()),
             ]
         )
 

diff --git a/tests/test_install.py b/tests/test_install.py
index 44f9032..5e2fa9b 100644
--- a/tests/test_install.py
+++ b/tests/test_install.py
@@ -86,7 +86,7 @@ def make_mock_geturl_download_archive(
 
     def mock_getUrl(url: str, *args) -> str:
         if url.endswith(updates_url):
-            qt_major_nodot = f"qt{qt_version[0]}.{qt_version.replace('.', '')}"
+            qt_major_nodot = "59" if qt_version == "5.9.0" else f"qt{qt_version[0]}.{qt_version.replace('.', '')}"
             _xml = textwrap.dedent(
                 f"""\
                 <Updates>
@@ -122,7 +122,8 @@ def make_mock_geturl_download_archive(
                     full_path.parent.mkdir(parents=True)
                 full_path.write_text(file[UNPATCHED_CONTENT], "utf_8")
 
-            archive.writeall(path=temp_path, arcname=qt_version)
+            archive_name = "5.9" if qt_version == "5.9.0" else qt_version
+            archive.writeall(path=temp_path, arcname=archive_name)
 
     return mock_getUrl, mock_download_archive
 
@@ -178,6 +179,66 @@ def disable_sockets_and_multiprocessing(monkeypatch):
                 r"Time elapsed: .* second"
             ),
         ),
+        (
+            "install 5.9.0 windows desktop win32_mingw53".split(),
+            "windows",
+            "desktop",
+            "5.9.0",
+            "win32_mingw53",
+            "mingw53_32",
+            "windows_x86/desktop/qt5_59/Updates.xml",
+            (
+                {
+                    FILENAME: "mkspecs/qconfig.pri",
+                    UNPATCHED_CONTENT: "... blah blah blah ...\n"
+                    "QT_EDITION = Not OpenSource\n"
+                    "QT_LICHECK = Not Empty\n"
+                    "... blah blah blah ...\n",
+                    PATCHED_CONTENT: "... blah blah blah ...\n"
+                    "QT_EDITION = OpenSource\n"
+                    "QT_LICHECK =\n"
+                    "... blah blah blah ...\n",
+                },
+            ),
+            re.compile(
+                r"^aqtinstall\(aqt\) v.* on Python 3.*\n"
+                r"Warning: The command 'install' is deprecated and marked for removal in a future version of aqt.\n"
+                r"In the future, please use the command 'install-qt' instead.\n"
+                r"Downloading qtbase...\n"
+                r"Finished installation of qtbase-windows-win32_mingw53.7z in .*\n"
+                r"Finished installation\n"
+                r"Time elapsed: .* second"
+            ),
+        ),
+        (
+            "install-qt windows desktop 5.9.0 win32_mingw53".split(),
+            "windows",
+            "desktop",
+            "5.9.0",
+            "win32_mingw53",
+            "mingw53_32",
+            "windows_x86/desktop/qt5_59/Updates.xml",
+            (
+                {
+                    FILENAME: "mkspecs/qconfig.pri",
+                    UNPATCHED_CONTENT: "... blah blah blah ...\n"
+                    "QT_EDITION = Not OpenSource\n"
+                    "QT_LICHECK = Not Empty\n"
+                    "... blah blah blah ...\n",
+                    PATCHED_CONTENT: "... blah blah blah ...\n"
+                    "QT_EDITION = OpenSource\n"
+                    "QT_LICHECK =\n"
+                    "... blah blah blah ...\n",
+                },
+            ),
+            re.compile(
+                r"^aqtinstall\(aqt\) v.* on Python 3.*\n"
+                r"Downloading qtbase...\n"
+                r"Finished installation of qtbase-windows-win32_mingw53.7z in .*\n"
+                r"Finished installation\n"
+                r"Time elapsed: .* second"
+            ),
+        ),
         (
             "install-qt windows desktop 5.14.0 win32_mingw73".split(),
             "windows",
@@ -289,6 +350,8 @@ def test_install(
         assert expect_out.match(err)
 
         installed_path = Path(output_dir) / version / arch_dir
+        if version == "5.9.0":
+            installed_path = Path(output_dir) / "5.9" / arch_dir
         assert installed_path.is_dir()
         for patched_file in files:
             file_path = installed_path / patched_file[FILENAME]

Qt 5.9 installation was broken at some point
`aqt install 5.9 linux desktop` returns "Invalid version string: '5.9'"

Qt 5.9 has a weird package name but it is hosted: https://download.qt.io/online/qtsdkrepository/linux_x64/desktop/qt5_59/

This worked in 1.1.3 but is broken in 1.2.x, as I discovered when trying to update the version.
https://github.com/jurplel/install-qt-action/runs/3303265869
tests/test_install.py::test_install[cmd1-windows-desktop-5.9.0-win32_mingw53-mingw53_32-windows_x86/desktop/qt5_59/Updates.xml-files1-^aqtinstall\\(aqt\\) tests/test_install.py::test_install[cmd2-windows-desktop-5.9.0-win32_mingw53-mingw53_32-windows_x86/desktop/qt5_59/Updates.xml-files2-^aqtinstall\\(aqt\\)
tests/test_install.py::test_install[cmd0-windows-desktop-5.14.0-win32_mingw73-mingw73_32-windows_x86/desktop/qt5_5140/Updates.xml-files0-^aqtinstall\\(aqt\\) tests/test_install.py::test_install[cmd3-windows-desktop-5.14.0-win32_mingw73-mingw73_32-windows_x86/desktop/qt5_5140/Updates.xml-files3-^aqtinstall\\(aqt\\) tests/test_install.py::test_install[cmd4-windows-android-6.1.0-android_armv7-android_armv7-windows_x86/android/qt6_610_armv7/Updates.xml-files4-^aqtinstall\\(aqt\\)