diff --git a/.gitignore b/.gitignore
index 319a6c5..f3f99be 100644
--- a/.gitignore
+++ b/.gitignore
@@ -153,3 +153,5 @@ cython_debug/
 
 output/
 .vscode/
+temp/
+config.ini
diff --git a/assets/iconEnabled.ico b/assets/icon.ico
similarity index 100%
rename from assets/iconEnabled.ico
rename to assets/icon.ico
diff --git a/config.ini b/config.ini
deleted file mode 100644
index 6daef17..0000000
--- a/config.ini
+++ /dev/null
@@ -1,7 +0,0 @@
-[Settings]
-monitor_name = LG TV
-monitor_serial = nan
-multimonitortool_executable = C:/App_Install/multimonitortool-x64/MultiMonitorTool.exe
-start_with_windows = no
-first_start = no
-
diff --git a/requirements.txt b/requirements.txt
index e10f191..0262081 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -2,4 +2,4 @@ win10toast
 pystray
 pandas
 customtkinter
-python-tkdnd
\ No newline at end of file
+CTkMessagebox
\ No newline at end of file
diff --git a/smct_pkg/config.py b/smct_pkg/config.py
index e16c7ee..f547096 100644
--- a/smct_pkg/config.py
+++ b/smct_pkg/config.py
@@ -1,12 +1,12 @@
 import configparser
 import os
+import sys
 
 from smct_pkg import (
-    multimonitortool,
     notification,
     paths,
     registry,
-    setup_gui,
+    ui,
     ui_strings,
 )
 
@@ -31,31 +31,22 @@
 
 
 def check_for_missing_files():
-    # Check for assets folder
-    if not os.path.exists(paths.ASSETS_DIR_PATH):
-        os.makedirs(paths.ASSETS_DIR_PATH)
     # Check for Icons
     if not os.path.exists(paths.ASSETS_ICON_ENABLED_PATH):
         notification.send_error(
             paths.ASSETS_ICON_ENABLED_PATH + ui_strings.FILE_NOT_FOUND
         )
+        sys.exit(1)
     if not os.path.exists(paths.ASSETS_ICON_DISABLED_PATH):
         notification.send_error(
             paths.ASSETS_ICON_DISABLED_PATH + ui_strings.FILE_NOT_FOUND
         )
-
-    # Check for MultiMonitorTool
-    if not os.path.exists(MMT_PATH_VALUE):
-        notification.send_error(MMT_PATH_VALUE + ui_strings.FILE_NOT_FOUND)
+        sys.exit(1)
 
     # Check for temp folder
     if not os.path.exists(paths.TEMP_DIR_PATH):
         os.makedirs(paths.TEMP_DIR_PATH)
 
-    # Check for MultiMonitorTool CSV
-    if not os.path.exists(paths.MMT_CSV_PATH):
-        multimonitortool.save_mmt_config()
-
 
 def read_config():
     # Check if config.ini file is present
@@ -75,18 +66,18 @@ def read_config():
     )
     FIRST_START_VALUE = _configparser.getboolean(SETTINGS_SECTION, FIRT_START_KEY)
 
+    check_for_missing_files()
+
     if START_WITH_WINDOWS_VALUE:
         registry.add_to_autostart()
     else:
         registry.remove_from_autostart()
 
     if FIRST_START_VALUE:
-        setup_gui.init_mmt_selection_frame()
+        ui.init_mmt_selection_frame()
         FIRST_START_VALUE = False
         set_config_value(SETTINGS_SECTION, FIRT_START_KEY, FIRST_START_VALUE)
 
-    check_for_missing_files()
-
 
 def _create_default_config_file():
     _configparser["Settings"] = {
diff --git a/smct_pkg/notification.py b/smct_pkg/notification.py
index 4606928..6ef5f23 100644
--- a/smct_pkg/notification.py
+++ b/smct_pkg/notification.py
@@ -1,18 +1,5 @@
-import threading
+from tkinter import messagebox
 
-from win10toast import ToastNotifier
 
-
-# TODO: add Logic
 def send_error(text):
-    toaster = ToastNotifier()
-    toaster.show_toast("Error", text, duration=7)
-
-
-def send_notification(text, duration):
-    def show_notification():
-        toaster = ToastNotifier()
-        toaster.show_toast("It's your first startup!", text, duration=duration)
-
-    notification_thread = threading.Thread(target=show_notification)
-    notification_thread.start()
+    messagebox.showerror("Error", text)
diff --git a/smct_pkg/paths.py b/smct_pkg/paths.py
index c2338f9..2771400 100644
--- a/smct_pkg/paths.py
+++ b/smct_pkg/paths.py
@@ -32,3 +32,4 @@ def strip_package_name_from_path(path):
 MMT_CONFIG_PATH = TEMP_DIR_PATH + r"\MultiMonitorToolConfig"
 ASSETS_ICON_ENABLED_PATH = ASSETS_DIR_PATH + r"\iconEnabled.png"
 ASSETS_ICON_DISABLED_PATH = ASSETS_DIR_PATH + r"\iconDisabled.png"
+ASSETS_ICO_PATH = ASSETS_DIR_PATH + r"\icon.ico"
diff --git a/smct_pkg/tray.py b/smct_pkg/tray.py
index b82712a..58d922c 100644
--- a/smct_pkg/tray.py
+++ b/smct_pkg/tray.py
@@ -8,8 +8,8 @@
 
 ICON = None
 
-icon_enabled_image = Image.open(paths.ASSETS_ICON_ENABLED_PATH)
-icon_disabled_image = Image.open(paths.ASSETS_ICON_DISABLED_PATH)
+ICON_ENABLED_IMAGE = None
+ICON_DISABLED_IMAGE = None
 
 
 def save_mmt_config_clicked():
@@ -19,10 +19,10 @@ def save_mmt_config_clicked():
 def icon_tray_clicked():
     if multimonitortool.is_monitor_enabled():
         multimonitortool.disable_monitor()
-        ICON.icon = icon_disabled_image
+        ICON.icon = ICON_DISABLED_IMAGE
     else:
         multimonitortool.enable_monitor()
-        ICON.icon = icon_enabled_image
+        ICON.icon = ICON_ENABLED_IMAGE
 
 
 def exit_clicked():
@@ -64,6 +64,11 @@ def startup_with_windows_clicked(icon):
 
 
 def init_tray():
+    # pylint: disable=global-statement
+    global ICON_ENABLED_IMAGE, ICON_DISABLED_IMAGE
+    ICON_ENABLED_IMAGE = Image.open(paths.ASSETS_ICON_ENABLED_PATH)
+    ICON_DISABLED_IMAGE = Image.open(paths.ASSETS_ICON_DISABLED_PATH)
+
     menu = (
         item(ui_strings.APP_NAME, icon_tray_clicked, default=True, visible=False),
         item(
@@ -84,11 +89,10 @@ def init_tray():
     first_image_icon = None
 
     if multimonitortool.is_monitor_enabled():
-        first_image_icon = icon_enabled_image
-        if not os.path.exists(paths.MMT_CONFIG_PATH):
-            multimonitortool.save_mmt_config()
+        first_image_icon = ICON_ENABLED_IMAGE
+        multimonitortool.save_mmt_config()
     else:
-        first_image_icon = icon_disabled_image
+        first_image_icon = ICON_DISABLED_IMAGE
 
     # pylint: disable=global-statement
     global ICON
diff --git a/smct_pkg/setup_gui.py b/smct_pkg/ui.py
similarity index 86%
rename from smct_pkg/setup_gui.py
rename to smct_pkg/ui.py
index ea73313..8a8cf15 100644
--- a/smct_pkg/setup_gui.py
+++ b/smct_pkg/ui.py
@@ -1,13 +1,10 @@
 import sys
+import os
+import shutil
 import tkinter
 import customtkinter
 from customtkinter import filedialog
-
-
-from smct_pkg import ui_strings, config, multimonitortool
-
-# https://github.com/TomSchimansky/CustomTkinter/tree/master/examples
-# https://github.com/TomSchimansky/CustomTkinter
+from smct_pkg import ui_strings, config, multimonitortool, paths
 
 customtkinter.set_ctk_parent_class(tkinter.Tk)
 
@@ -18,14 +15,19 @@
 
 _root_window = customtkinter.CTk()
 
-_root_window.title(ui_strings.APP_NAME)
+_root_window.title(ui_strings.SHORT_NAME)
 _root_window.resizable(False, False)
 
+_root_window.geometry()
+
 _select_mmt_exe_frame = customtkinter.CTkFrame(master=_root_window)
 _select_monitor_frame = customtkinter.CTkFrame(master=_root_window)
 
 
 def exit_application():
+    # clean up files if setup was interrupted
+    shutil.rmtree(paths.TEMP_DIR_PATH)
+    os.remove(paths.CONFIG_PATH)
     _root_window.destroy()
     sys.exit(1)
 
@@ -34,7 +36,8 @@ def exit_application():
 
 
 def init_mmt_selection_frame():
-    _root_window.geometry("300x110")
+    _root_window.iconbitmap(paths.ASSETS_ICO_PATH)
+    # _root_window.geometry("300x110")
     _select_mmt_exe_frame.pack(pady=10, padx=10, fill="both", expand=True)
 
     select_mmt_label = customtkinter.CTkLabel(
@@ -59,9 +62,6 @@ def _browse_button_callback():
         title=ui_strings.SELECT_MMT_LABEL,
         filetypes=[("MultiMonitorTool", "multimonitortool.exe")],
     )
-    # TODO: if using auto-py-to-exe this returns the wrong path? -> crashes
-    # C:/App_Install/multimonitortool-x64/MultiMonitorTool.exe should the output be
-    # but its C:\\App_Install\\ etc. fix this.
     if not _exe_path:
         print(ui_strings.NO_FILE_SELECTED)
     else:
@@ -76,7 +76,7 @@ def _browse_button_callback():
 
 
 def _init_monitor_selection_frame():
-    _root_window.geometry("300x160")
+    # _root_window.geometry("300x160")
     _select_monitor_frame.pack(pady=10, padx=10, fill="both", expand=True)
 
     _monitor_selection_label = customtkinter.CTkLabel(
diff --git a/smct_pkg/ui_strings.py b/smct_pkg/ui_strings.py
index a11b642..6ead045 100644
--- a/smct_pkg/ui_strings.py
+++ b/smct_pkg/ui_strings.py
@@ -1,7 +1,8 @@
 APP_NAME = "SimpleMonitorControlTray"
+SHORT_NAME = "SMCT"
 
 # UI STRINGS TRAY
-FILE_NOT_FOUND = " file not found. Exiting."
+FILE_NOT_FOUND = " not found. Exiting."
 
 STARTUP_WITH_WINDOWS = "Startup with Windows"
 SAVE_MONITOR_LAYOUT = "Save current monitor layout"
@@ -10,7 +11,7 @@
 
 # GUI STRINGS
 SELECT_MMT_LABEL = "Please select your MultiMonitorTool.exe"
-SELECT_MONITOR_LABEL = "Select a monitor."
+SELECT_MONITOR_LABEL = "Select the monitor that will be turned off."
 NO_FILE_SELECTED = "No file selected. Please select multimonitortool.exe"
 BROWSE_BUTTON = "Browse..."
 OK_BUTTON = "OK"
diff --git a/temp/MultiMonitorToolConfig b/temp/MultiMonitorToolConfig
deleted file mode 100644
index 5603a76..0000000
--- a/temp/MultiMonitorToolConfig
+++ /dev/null
@@ -1,36 +0,0 @@
-[Monitor0]
-Name=\\.\DISPLAY1
-MonitorID=MONITOR\LEN66FB\{4d36e96e-e325-11ce-bfc1-08002be10318}\0008
-SerialNumber=URHK6FCP
-BitsPerPixel=32
-Width=2560
-Height=1440
-DisplayFlags=0
-DisplayFrequency=60
-DisplayOrientation=0
-PositionX=2560
-PositionY=0
-[Monitor1]
-Name=\\.\DISPLAY2
-MonitorID=MONITOR\ACI27EC\{4d36e96e-e325-11ce-bfc1-08002be10318}\0009
-SerialNumber=#ASNImfyQBwHd
-BitsPerPixel=32
-Width=2560
-Height=1440
-DisplayFlags=0
-DisplayFrequency=144
-DisplayOrientation=0
-PositionX=0
-PositionY=0
-[Monitor2]
-Name=\\.\DISPLAY3
-MonitorID=MONITOR\GSM0001\{4d36e96e-e325-11ce-bfc1-08002be10318}\0010
-SerialNumber=
-BitsPerPixel=32
-Width=1920
-Height=1080
-DisplayFlags=0
-DisplayFrequency=60
-DisplayOrientation=0
-PositionX=1635
-PositionY=-1080
diff --git a/temp/MultiMonitorToolOutput.csv b/temp/MultiMonitorToolOutput.csv
deleted file mode 100644
index eae1627..0000000
--- a/temp/MultiMonitorToolOutput.csv
+++ /dev/null
@@ -1,4 +0,0 @@
-Resolution,Left-Top,Right-Bottom,Active,Disconnected,Primary,Colors,Frequency,Orientation,Maximum Resolution,Name,Adapter,Device ID,Device Key,Monitor ID,Short Monitor ID,Monitor Key,Monitor String,Monitor Name,Monitor Serial Number
-0 X 0,"0, 0","0, 0",No,No,No,0,0,Default,1920 X 1080,\\.\DISPLAY3,NVIDIA GeForce RTX 2080 Ti,PCI\VEN_10DE&DEV_1E07&SUBSYS_866A1043&REV_A1,\Registry\Machine\System\CurrentControlSet\Control\Video\{3AB1B141-D3F6-11EE-A460-106FD93C4F11}\0002,MONITOR\GSM0001\{4d36e96e-e325-11ce-bfc1-08002be10318}\0010,GSM0001,\Registry\Machine\System\CurrentControlSet\Control\Class\{4d36e96e-e325-11ce-bfc1-08002be10318}\0010,Generic PnP Monitor,LG TV,
-2560 X 1440,"0, 0","2560, 1440",Yes,No,Yes,32,144,Default,2560 X 1440,\\.\DISPLAY2,NVIDIA GeForce RTX 2080 Ti,PCI\VEN_10DE&DEV_1E07&SUBSYS_866A1043&REV_A1,\Registry\Machine\System\CurrentControlSet\Control\Video\{3AB1B141-D3F6-11EE-A460-106FD93C4F11}\0001,MONITOR\ACI27EC\{4d36e96e-e325-11ce-bfc1-08002be10318}\0009,ACI27EC,\Registry\Machine\System\CurrentControlSet\Control\Class\{4d36e96e-e325-11ce-bfc1-08002be10318}\0009,ROG PG279Q,ROG PG279Q,#ASNImfyQBwHd
-2560 X 1440,"2560, 0","5120, 1440",Yes,No,No,32,60,Default,2560 X 1440,\\.\DISPLAY1,NVIDIA GeForce RTX 2080 Ti,PCI\VEN_10DE&DEV_1E07&SUBSYS_866A1043&REV_A1,\Registry\Machine\System\CurrentControlSet\Control\Video\{3AB1B141-D3F6-11EE-A460-106FD93C4F11}\0000,MONITOR\LEN66FB\{4d36e96e-e325-11ce-bfc1-08002be10318}\0008,LEN66FB,\Registry\Machine\System\CurrentControlSet\Control\Class\{4d36e96e-e325-11ce-bfc1-08002be10318}\0008,Generic PnP Monitor,C27q-35,URHK6FCP
diff --git a/temp/sampleoutput.csv b/temp/sampleoutput.csv
deleted file mode 100644
index 3b3ba3b..0000000
--- a/temp/sampleoutput.csv
+++ /dev/null
@@ -1,4 +0,0 @@
-Resolution,Left-Top,Right-Bottom,Active,Disconnected,Primary,Colors,Frequency,Orientation,Maximum Resolution,Name,Adapter,Device ID,Device Key,Monitor ID,Short Monitor ID,Monitor Key,Monitor String,Monitor Name,Monitor Serial Number
-0 X 0,"0, 0","0, 0",No,No,No,0,0,Default,2560 X 1440,\\.\DISPLAY3,NVIDIA GeForce RTX 2080 Ti,PCI\VEN_10DE&DEV_1E07&SUBSYS_866A1043&REV_A1,\Registry\Machine\System\CurrentControlSet\Control\Video\{3AB1B141-D3F6-11EE-A460-106FD93C4F11}\0002,MONITOR\ACI27EC\{4d36e96e-e325-11ce-bfc1-08002be10318}\0009,ACI27EC,\Registry\Machine\System\CurrentControlSet\Control\Class\{4d36e96e-e325-11ce-bfc1-08002be10318}\0009,ROG PG279Q,ROG PG279Q,#ASNImfyQBwHd
-1920 X 1080,"-959, -1080","961, 0",Yes,No,No,32,60,Default,1920 X 1080,\\.\DISPLAY2,NVIDIA GeForce RTX 2080 Ti,PCI\VEN_10DE&DEV_1E07&SUBSYS_866A1043&REV_A1,\Registry\Machine\System\CurrentControlSet\Control\Video\{3AB1B141-D3F6-11EE-A460-106FD93C4F11}\0001,MONITOR\GSM0001\{4d36e96e-e325-11ce-bfc1-08002be10318}\0010,GSM0001,\Registry\Machine\System\CurrentControlSet\Control\Class\{4d36e96e-e325-11ce-bfc1-08002be10318}\0010,Generic PnP Monitor,LG TV,
-2560 X 1440,"0, 0","2560, 1440",Yes,No,Yes,32,60,Default,2560 X 1440,\\.\DISPLAY1,NVIDIA GeForce RTX 2080 Ti,PCI\VEN_10DE&DEV_1E07&SUBSYS_866A1043&REV_A1,\Registry\Machine\System\CurrentControlSet\Control\Video\{3AB1B141-D3F6-11EE-A460-106FD93C4F11}\0000,MONITOR\LEN66FB\{4d36e96e-e325-11ce-bfc1-08002be10318}\0008,LEN66FB,\Registry\Machine\System\CurrentControlSet\Control\Class\{4d36e96e-e325-11ce-bfc1-08002be10318}\0008,Generic PnP Monitor,C27q-35,URHK6FCP