diff --git a/pyproject.toml b/pyproject.toml
index e782ac8..e140bda 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -31,7 +31,7 @@ dependencies = [
     'psutil<5.10',
     'pyyaml<6.1',
     'pywin32<=306; sys_platform == "win32"',
-    'httpx<0.28',
+    'requests',
     'platformdirs<=4.2.2',
     'uvicorn',
 ]
@@ -52,7 +52,6 @@ dependencies = [
     "pytest-datadir",
     "fastapi",
     "pyinstaller",
-    "httpx==0.27.0",
     "requests",
     "platformdirs==4.2.2",
     "uvicorn",
@@ -79,7 +78,7 @@ dependencies = [
     "mypy>=1.0.0",
     "fastapi",
     "pyinstaller",
-    "httpx==0.27.0"
+    "requests"
 ]
 [tool.hatch.envs.types.scripts]
 check = "mypy --install-types --non-interactive {args:src/antares_web_installer tests}"
diff --git a/pytest.ini b/pytest.ini
new file mode 100644
index 0000000..e69de29
diff --git a/src/antares_web_installer/app.py b/src/antares_web_installer/app.py
index ac98895..8961a46 100644
--- a/src/antares_web_installer/app.py
+++ b/src/antares_web_installer/app.py
@@ -5,12 +5,12 @@
 import textwrap
 import time
 import webbrowser
-
 from difflib import SequenceMatcher
 from pathlib import Path
 from shutil import copy2, copytree
+from typing import List
 
-import httpx
+import requests
 
 if os.name == "nt":
     from pythoncom import com_error
@@ -31,6 +31,9 @@
 SHORTCUT_NAMES = {"posix": "AntaresWebServer.desktop", "nt": "AntaresWebServer.lnk"}
 
 SERVER_ADDRESS = "http://127.0.0.1:8080"
+HEALTHCHECK_ADDRESS = f"{SERVER_ADDRESS}/api/health"
+
+MAX_SERVER_START_TIME = 60
 
 
 class InstallError(Exception):
@@ -54,7 +57,7 @@ class App:
     def __post_init__(self):
         # Prepare the path to the executable which is located in the target directory
         server_name = SERVER_NAMES[os.name]
-        self.server_path = self.target_dir.joinpath("AntaresWeb", server_name)
+        self.server_path = self.target_dir / "AntaresWeb" / server_name
 
         # Set all progress variables needed to compute current progress of the installation
         self.nb_steps = 2  # kill, install steps
@@ -95,35 +98,43 @@ def kill_running_server(self) -> None:
         Check whether Antares service is up.
         Kill the process if so.
         """
-        processes_list = list(psutil.process_iter(["pid", "name"]))
-        processes_list_length = len(processes_list)
+        server_processes = self._get_server_processes()
+        if len(server_processes) > 0:
+            logger.info("Attempt to stop running Antares server ...")
+            for p in server_processes:
+                try:
+                    p.kill()
+                except psutil.NoSuchProcess:
+                    logger.debug(f"The process '{p.pid}' was stopped before being killed.")
+                    continue
+            gone, alive = psutil.wait_procs(server_processes, timeout=5)
+            alive_count = len(alive)
+            if alive_count > 0:
+                raise InstallError(
+                    "Could not to stop Antares server. Please stop it before launching again the installation."
+                )
+            else:
+                logger.info("Antares server successfully stopped...")
+        else:
+            logger.info("No running server found, resuming installation.")
+        self.update_progress(100)
 
-        for index, proc in enumerate(processes_list):
-            # evaluate matching between query process name and existing process name
+    def _get_server_processes(self) -> List[psutil.Process]:
+        res = []
+        for process in psutil.process_iter(["pid", "name"]):
             try:
-                matching_ratio = SequenceMatcher(None, "antareswebserver", proc.name().lower()).ratio()
+                # evaluate matching between query process name and existing process name
+                matching_ratio = SequenceMatcher(None, "antareswebserver", process.name().lower()).ratio()
             except FileNotFoundError:
-                logger.warning("The process '{}' does not exist anymore. Skipping its analysis".format(proc.name()))
+                logger.warning("The process '{}' does not exist anymore. Skipping its analysis".format(process.name()))
                 continue
             except psutil.NoSuchProcess:
-                logger.warning("The process '{}' was stopped before being analyzed. Skipping.".format(proc.name()))
+                logger.warning("The process '{}' was stopped before being analyzed. Skipping.".format(process.name()))
                 continue
             if matching_ratio > 0.8:
-                logger.info("Running server found. Attempt to stop it ...")
-                logger.debug(f"Server process:{proc.name()} -  process id: {proc.pid}")
-                running_app = psutil.Process(pid=proc.pid)
-                running_app.kill()
-
-                try:
-                    running_app.wait(5)
-                except psutil.TimeoutExpired as e:
-                    raise InstallError(
-                        "Impossible to kill the server. Please kill it manually before relaunching the installer."
-                    ) from e
-                else:
-                    logger.info("The application was successfully stopped.")
-            self.update_progress((index + 1) * 100 / processes_list_length)
-        logger.info("No other processes found.")
+                res.append(process)
+                logger.debug(f"Running server found: {process.name()} -  process id: {process.pid}")
+        return res
 
     def install_files(self):
         """ """
@@ -254,7 +265,7 @@ def create_shortcuts(self):
                 description="Launch Antares Web Server in background",
             )
         except com_error as e:
-            raise InstallError("Impossible to create a new shortcut: {}\nSkip shortcut creation".format(e))
+            raise InstallError(f"Impossible to create a new shortcut: {e}\nSkipping shortcut creation") from e
         else:
             assert shortcut_path in list(desktop_path.iterdir())
             logger.info(f"Server shortcut {shortcut_path} was successfully created.")
@@ -270,42 +281,33 @@ def start_server(self):
         args = [self.server_path]
         server_process = subprocess.Popen(
             args=args,
-            stdin=subprocess.PIPE,
-            stdout=subprocess.PIPE,
-            stderr=subprocess.STDOUT,
             cwd=self.target_dir,
+            stdout=subprocess.DEVNULL,
+            stderr=subprocess.DEVNULL,
             shell=True,
         )
         self.update_progress(50)
 
-        if not server_process.poll():
-            logger.info("Server is starting up ...")
-        else:
-            stdout, stderr = server_process.communicate()
-            msg = f"The server unexpectedly stopped running. (code {server_process.returncode})"
-            logger.info(msg)
-            logger.info(f"Server unexpectedly stopped.\nstdout: {stdout}\nstderr: {stderr}")
-            raise InstallError(msg)
-
-        nb_attempts = 0
-        max_attempts = 10
-
-        while nb_attempts < max_attempts:
-            logger.info(f"Attempt #{nb_attempts}...")
+        start_time = time.time()
+        nb_attempts = 1
+        while time.time() - start_time < MAX_SERVER_START_TIME:
+            logger.info(f"Waiting for server start (attempt #{nb_attempts})...")
+            if server_process.poll() is not None:
+                raise InstallError("Server failed to start, please check server logs.")
             try:
-                res = httpx.get(SERVER_ADDRESS + "/health", timeout=1)
+                res = requests.get(HEALTHCHECK_ADDRESS)
                 if res.status_code == 200:
                     logger.info("The server is now running.")
                     break
-            except httpx.RequestError:
-                time.sleep(1)
+                else:
+                    logger.debug(f"Got HTTP status code {res.status_code} while requesting {HEALTHCHECK_ADDRESS}")
+                    logger.debug(f"Content: {res.text}")
+            except requests.RequestException as req_err:
+                logger.debug(f"Error while requesting {HEALTHCHECK_ADDRESS}: {req_err}", exc_info=req_err)
+            time.sleep(1)
             nb_attempts += 1
         else:
-            stdout, stderr = server_process.communicate()
-            msg = "The server didn't start in time"
-            logger.error(msg)
-            logger.error(f"stdout: {stdout}\nstderr: {stderr}")
-            raise InstallError(msg)
+            raise InstallError("Server didn't start in time, please check server logs.")
 
     def open_browser(self):
         """
diff --git a/src/antares_web_installer/config/__init__.py b/src/antares_web_installer/config/__init__.py
index a16fc7b..5fdaa15 100644
--- a/src/antares_web_installer/config/__init__.py
+++ b/src/antares_web_installer/config/__init__.py
@@ -29,5 +29,8 @@ def update_config(source_path: Path, target_path: Path, version: str) -> None:
             with target_path.open("r") as f:
                 config = yaml.safe_load(f)
 
+    if version_info < (2, 18):
+        update_to_2_15(config)
+
     with source_path.open(mode="w") as f:
         yaml.dump(config, f)
diff --git a/src/antares_web_installer/config/config_2_18.py b/src/antares_web_installer/config/config_2_18.py
new file mode 100644
index 0000000..538152d
--- /dev/null
+++ b/src/antares_web_installer/config/config_2_18.py
@@ -0,0 +1,10 @@
+import typing as t
+
+
+def update_to_2_18(config: t.MutableMapping[str, t.Any]) -> None:
+    """
+    Update the configuration file to version 2.18 in-place:
+    we need to ensure root_path is / and api_prefix is /api
+    """
+    del config["root_path"]
+    config["api_prefix"] = "/api"
diff --git a/src/antares_web_installer/gui/__main__.py b/src/antares_web_installer/gui/__main__.py
old mode 100644
new mode 100755
diff --git a/src/antares_web_installer/gui/controller.py b/src/antares_web_installer/gui/controller.py
index 8afd4a7..d05dc4c 100644
--- a/src/antares_web_installer/gui/controller.py
+++ b/src/antares_web_installer/gui/controller.py
@@ -6,27 +6,21 @@
 import typing
 from pathlib import Path
 from threading import Thread
-
-from antares_web_installer.gui.mvc import Controller, ControllerError
-from antares_web_installer.gui.model import WizardModel
-from antares_web_installer.gui.view import WizardView
+from typing import Optional
 
 from antares_web_installer import logger
 from antares_web_installer.app import App, InstallError
 from antares_web_installer.gui.logger import ConsoleHandler, ProgressHandler, LogFileHandler
+from antares_web_installer.gui.model import WizardModel
+from antares_web_installer.gui.mvc import Controller
+from antares_web_installer.gui.view import WizardView
 
 
-class InstallationThread(Thread):
-    def __init__(self, group=None, target=None, name=None, args=(), kwargs=None, *, daemon=None):
-        super().__init__(group, target, name, args, kwargs, daemon=daemon)
-
-    def run(self):
-        try:
-            super().run()
-        except OSError as e:
-            raise e
-        except InstallError as e:
-            raise e
+def run_installation(app: App) -> None:
+    try:
+        app.run()
+    except Exception as e:
+        logger.exception(f"An error occurred during installation: {e}")
 
 
 class WizardController(Controller):
@@ -39,8 +33,8 @@ class WizardController(Controller):
     def __init__(self):
         super().__init__()
         self.app = None
-        self.log_dir = None
-        self.log_file = None
+        self.log_dir: Optional[Path] = None
+        self.log_file: Optional[Path] = None
 
         # init loggers
         self.logger = logger
@@ -64,17 +58,18 @@ def init_view(self) -> "WizardView":
         return WizardView(self)
 
     def init_file_handler(self):
-        self.log_dir = self.model.target_dir.joinpath("logs/")
+        self.log_dir: Path = self.model.target_dir / "logs"
         tmp_file_name = "wizard.log"
 
         if not self.log_dir.exists():
-            self.log_dir = self.model.source_dir.joinpath("logs/")  # use the source directory as tmp dir for logs
+            self.log_dir = self.model.source_dir / "logs"  # use the source directory as tmp dir for logs
             self.logger.debug(
                 "No log directory found with path '{}'. Attempt to generate the path.".format(self.log_dir)
             )
+            self.log_dir.mkdir(parents=True, exist_ok=True)
             self.logger.info("Path '{}' was successfully created.".format(self.log_dir))
 
-        self.log_file = self.log_dir.joinpath(tmp_file_name)
+        self.log_file = self.log_dir / tmp_file_name
 
         # check if file exists
         if self.log_file not in list(self.log_dir.iterdir()):
@@ -140,29 +135,18 @@ def install(self, callback: typing.Callable):
             logger.warning("Impossible to create a new shortcut. Skip this step.")
             logger.debug(e)
 
-        thread = InstallationThread(target=self.app.run, args=())
+        self.thread = Thread(target=lambda: run_installation(self.app), args=())
 
         try:
-            thread.run()
+            self.thread.start()
         except InstallError as e:
             self.view.raise_error(e)
 
-    def installation_over(self) -> None:
-        """
-        This method makes sure the thread terminated. If not, it waits for it to terminate.
-        """
-        if self.thread:
-            while self.thread.join():
-                if not self.thread.is_alive():
-                    break
-
     def get_target_dir(self) -> Path:
         return self.model.target_dir
 
-    def set_target_dir(self, path: Path):
-        result = self.model.set_target_dir(path)
-        if not result:
-            raise ControllerError("Path '{}' is not a directory.".format(path))
+    def set_target_dir(self, path: Path) -> None:
+        self.model.set_target_dir(path)
 
     def get_shortcut(self) -> bool:
         return self.model.shortcut
diff --git a/src/antares_web_installer/gui/logger.py b/src/antares_web_installer/gui/logger.py
index e98d72e..3b253cf 100644
--- a/src/antares_web_installer/gui/logger.py
+++ b/src/antares_web_installer/gui/logger.py
@@ -2,8 +2,11 @@
 import typing
 
 
+MessageConsumer = typing.Callable[[str], None]
+
+
 class ConsoleHandler(logging.Handler):
-    def __init__(self, callback: typing.Callable):
+    def __init__(self, callback: MessageConsumer):
         logging.Handler.__init__(self)
         self.setLevel(logging.INFO)
         formatter = logging.Formatter("[%(asctime)-15s] %(message)s")
@@ -15,7 +18,7 @@ def emit(self, logs: logging.LogRecord):
 
 
 class ProgressHandler(logging.Handler):
-    def __init__(self, callback: typing.Callable):
+    def __init__(self, callback: MessageConsumer):
         """
         This logging handler intercept all logs that are progression values
         @param progress_var: tkinter.StringVar
diff --git a/src/antares_web_installer/gui/mvc.py b/src/antares_web_installer/gui/mvc.py
index fb9bf7c..8d3455a 100644
--- a/src/antares_web_installer/gui/mvc.py
+++ b/src/antares_web_installer/gui/mvc.py
@@ -6,6 +6,8 @@
 from __future__ import annotations
 
 import tkinter as tk
+import traceback
+from tkinter import messagebox
 
 
 class Model:
@@ -35,6 +37,11 @@ class View(tk.Tk):
     def __init__(self, controller: Controller):
         super().__init__()
         self.controller = controller
+        self.report_callback_exception = self.show_error
+
+    def show_error(self, *args):
+        err = traceback.format_exception(*args)
+        messagebox.showerror("Exception", "".join(err))
 
 
 class ControllerError(Exception):
diff --git a/src/antares_web_installer/gui/view.py b/src/antares_web_installer/gui/view.py
index e85f1f0..2dc140e 100644
--- a/src/antares_web_installer/gui/view.py
+++ b/src/antares_web_installer/gui/view.py
@@ -154,11 +154,7 @@ def get_target_dir(self) -> Path:
         return self.controller.get_target_dir()
 
     def set_target_dir(self, new_target_dir: str):
-        try:
-            self.controller.set_target_dir(Path(new_target_dir))
-        except ControllerError as e:
-            logger.warning("Path is not valid: {}".format(e))
-            self.raise_warning("Path selected is not valid")
+        self.controller.set_target_dir(Path(new_target_dir))
 
     def get_launch(self) -> bool:
         return self.controller.get_launch()
@@ -188,5 +184,4 @@ def run_installation(self, callback):
         self.controller.install(callback)
 
     def installation_over(self):
-        self.controller.installation_over()
         self.frames["progress_frame"].installation_over()
diff --git a/src/antares_web_installer/gui/widgets/frame.py b/src/antares_web_installer/gui/widgets/frame.py
index e7234e9..9bd42a9 100644
--- a/src/antares_web_installer/gui/widgets/frame.py
+++ b/src/antares_web_installer/gui/widgets/frame.py
@@ -280,5 +280,5 @@ def __init__(self, master: tk.Misc, window: "WizardView", *args, **kwargs):
             style="Description.TLabel",
         ).pack(side="top", fill="x")
 
-        self.control_btn = ControlFrame(parent=self, window=window, finish_btn=True)
+        self.control_btn = ControlFrame(parent=self, window=window, cancel_btn=False, finish_btn=True)
         self.control_btn.pack(side="bottom", fill="x")
diff --git a/src/antares_web_installer/shortcuts/_win32_shell.py b/src/antares_web_installer/shortcuts/_win32_shell.py
index 205095a..e146b6a 100644
--- a/src/antares_web_installer/shortcuts/_win32_shell.py
+++ b/src/antares_web_installer/shortcuts/_win32_shell.py
@@ -11,13 +11,12 @@
 
 import os
 import typing as t
+from contextlib import contextmanager
 
+import pythoncom
 import win32com.client
 from win32com.shell import shell, shellcon
 
-_WSHELL = win32com.client.Dispatch("Wscript.Shell")
-
-
 # Windows Special Folders
 # see: https://docs.microsoft.com/en-us/windows/win32/shell/csidl
 
@@ -42,6 +41,15 @@ def get_start_menu() -> str:
     return shell.SHGetFolderPath(0, shellcon.CSIDL_PROGRAMS, None, 0)  # type: ignore
 
 
+@contextmanager
+def initialize_com():
+    try:
+        pythoncom.CoInitialize()
+        yield
+    finally:
+        pythoncom.CoUninitialize()
+
+
 def create_shortcut(
     target: t.Union[str, os.PathLike],
     exe_path: t.Union[str, os.PathLike],
@@ -56,13 +64,15 @@ def create_shortcut(
     if isinstance(arguments, str):
         arguments = [arguments] if arguments else []
 
-    wscript = _WSHELL.CreateShortCut(str(target))
-    wscript.TargetPath = str(exe_path)
-    wscript.Arguments = " ".join(arguments)
-    wscript.WorkingDirectory = str(working_dir)
-    wscript.WindowStyle = 0
-    if description:
-        wscript.Description = description
-    if icon_path:
-        wscript.IconLocation = str(icon_path)
-    wscript.save()
+    with initialize_com():
+        _WSHELL = win32com.client.Dispatch("Wscript.Shell")
+        wscript = _WSHELL.CreateShortCut(str(target))
+        wscript.TargetPath = str(exe_path)
+        wscript.Arguments = " ".join(arguments)
+        wscript.WorkingDirectory = str(working_dir)
+        wscript.WindowStyle = 0
+        if description:
+            wscript.Description = description
+        if icon_path:
+            wscript.IconLocation = str(icon_path)
+        wscript.save()
diff --git a/tests/config/test_config_2_18.py b/tests/config/test_config_2_18.py
new file mode 100644
index 0000000..c6a1201
--- /dev/null
+++ b/tests/config/test_config_2_18.py
@@ -0,0 +1,12 @@
+from pathlib import Path
+
+import yaml
+
+from antares_web_installer.config.config_2_18 import update_to_2_18
+
+
+def test_update_to_2_18(datadir: Path) -> None:
+    config = yaml.safe_load(datadir.joinpath("application-2.17.yaml").read_text())
+    expected = yaml.safe_load(datadir.joinpath("application-2.18.yaml").read_text())
+    update_to_2_18(config)
+    assert config == expected
diff --git a/tests/config/test_config_2_18/application-2.17.yaml b/tests/config/test_config_2_18/application-2.17.yaml
new file mode 100644
index 0000000..7641da3
--- /dev/null
+++ b/tests/config/test_config_2_18/application-2.17.yaml
@@ -0,0 +1,42 @@
+security:
+  disabled: false
+  jwt:
+    key: super-secret
+  login:
+    admin:
+      pwd: admin
+
+db:
+  url: "sqlite:////home/john/antares_data/database.db"
+
+storage:
+  tmp_dir: /tmp
+  matrixstore: /home/john/antares_data/matrices
+  archive_dir: /home/john/antares_data/archives
+  allow_deletion: false
+  workspaces:
+    default:
+      path: /home/john/antares_data/internal_studies/
+    studies:
+      path: /home/john/antares_data/studies/
+
+launcher:
+  default: local
+  local:
+    binaries:
+      850: /home/john/opt/antares-8.5.0-Ubuntu-20.04/antares-solver
+      860: /home/john/opt/antares-8.6.0-Ubuntu-20.04/antares-8.6-solver
+    enable_nb_cores_detection: True
+
+debug: false
+
+root_path: "/api"
+
+server:
+  worker_threadpool_size: 12
+  services:
+    - watcher
+    - matrix_gc
+
+logging:
+  level: INFO
diff --git a/tests/config/test_config_2_18/application-2.18.yaml b/tests/config/test_config_2_18/application-2.18.yaml
new file mode 100644
index 0000000..2a6d796
--- /dev/null
+++ b/tests/config/test_config_2_18/application-2.18.yaml
@@ -0,0 +1,42 @@
+security:
+  disabled: false
+  jwt:
+    key: super-secret
+  login:
+    admin:
+      pwd: admin
+
+db:
+  url: "sqlite:////home/john/antares_data/database.db"
+
+storage:
+  tmp_dir: /tmp
+  matrixstore: /home/john/antares_data/matrices
+  archive_dir: /home/john/antares_data/archives
+  allow_deletion: false
+  workspaces:
+    default:
+      path: /home/john/antares_data/internal_studies/
+    studies:
+      path: /home/john/antares_data/studies/
+
+launcher:
+  default: local
+  local:
+    binaries:
+      850: /home/john/opt/antares-8.5.0-Ubuntu-20.04/antares-solver
+      860: /home/john/opt/antares-8.6.0-Ubuntu-20.04/antares-8.6-solver
+    enable_nb_cores_detection: True
+
+debug: false
+
+api_prefix: "/api"
+
+server:
+  worker_threadpool_size: 12
+  services:
+    - watcher
+    - matrix_gc
+
+logging:
+  level: INFO
diff --git a/tests/integration/server_mock/web.py b/tests/integration/server_mock/web.py
index b484601..f29c0ca 100644
--- a/tests/integration/server_mock/web.py
+++ b/tests/integration/server_mock/web.py
@@ -30,7 +30,7 @@ async def lifespan(_unused_app: FastAPI) -> t.AsyncGenerator[None, None]:
 app = FastAPI(lifespan=lifespan)
 
 
-@app.get("/health")
+@app.get("/api/health")
 async def health():
     """
     Endpoint to check that the server is ready.
diff --git a/tests/integration/test_run_server.py b/tests/integration/test_run_server.py
index 84063fe..5b7a1ce 100644
--- a/tests/integration/test_run_server.py
+++ b/tests/integration/test_run_server.py
@@ -1,8 +1,9 @@
-import httpx  # type: ignore
-import subprocess
 import socket
+import subprocess
 import time
 
+import requests  # type: ignore
+
 SPAWN_TIMEOUT = 10
 """Timeout in seconds to wait for the server process to start."""
 
@@ -67,7 +68,7 @@ def test_server_health(antares_web_server_paths):
         else:
             raise RuntimeError("The server did not start in time.")
 
-        res = httpx.get("http://localhost:8080/health", timeout=0.25)
+        res = requests.get("http://localhost:8080/api/health", timeout=0.25)
         assert res.status_code == 200, res.json()
         assert res.json() == {"status": "available"}