diff --git a/Installation/Windows/Plugins/AddToPath.nsh b/Installation/Windows/Plugins/AddToPath.nsh
index b2c8b84c40..37e50df07c 100644
--- a/Installation/Windows/Plugins/AddToPath.nsh
+++ b/Installation/Windows/Plugins/AddToPath.nsh
@@ -1,4 +1,5 @@
 !include "StrStr.nsh"
+Var PathToAdd
 
 ;--------------------------------
 ; path functions
diff --git a/Installation/Windows/Plugins/exitcodes.nsh b/Installation/Windows/Plugins/exitcodes.nsh
index f108348a06..dc29490a73 100644
--- a/Installation/Windows/Plugins/exitcodes.nsh
+++ b/Installation/Windows/Plugins/exitcodes.nsh
@@ -1,78 +1,91 @@
 
 !include "LogicLib.nsh"
-!macro printExitCode exitCode Message
+!define ARANGO_EXIT_SUCCESS 0
+!define ARANGO_EXIT_FAILED 1
+!define ARANGO_EXIT_CODE_RESOLVING_FAILED 2
+!define ARANGO_EXIT_BINARY_NOT_FOUND 5
+!define ARANGO_EXIT_CONFIG_NOT_FOUND 6
+!define ARANGO_EXIT_UPGRADE_FAILED 10
+!define ARANGO_EXIT_UPGRADE_REQUIRED 11
+!define ARANGO_EXIT_DOWNGRADE_REQUIRED 12
+!define ARANGO_EXIT_VERSION_CHECK_FAILED 13
+!define ARANGO_EXIT_ALREADY_RUNNING 20
+!define ARANGO_EXIT_COULD_NOT_BIND_PORT 21
+!define ARANGO_EXIT_COULD_NOT_LOCK 22
+!define ARANGO_EXIT_RECOVERY 23
+!define ARANGO_EXIT_DB_NOT_EMPTY 24
+
+!macro printExitCode exitCode Message DetailMessage
   Push "${exitCode}"
   Push "${Message}"
+  Push "${DetailMessage}"
   Call printExitCode
 !macroend
 Function printExitCode
-pop $1
+pop $3
 pop $2
-${Switch} $0
+pop $1
+${Switch} $1
 
 
   ${Case} 0 # EXIT_SUCCESS
-    MessageBox MB_ICONEXCLAMATION '$1:$\r$\nsuccess'
-    ; No error has occurred.
+    MessageBox MB_ICONEXCLAMATION '$2:$\r$\n>> success <<$\r$\n"No error has occurred."$\r$\n$3'
   ${Break}
 
   ${Case} 1 # EXIT_FAILED
-    MessageBox MB_ICONEXCLAMATION '$1:$\r$\nexit with error'
-    ; Will be returned when a general error occurred.
+    MessageBox MB_ICONEXCLAMATION '$2:$\r$\n>> exit with error <<$\r$\n"Will be returned when a general error occurred."$\r$\n$3'
   ${Break}
 
   ${Case} 2 # EXIT_CODE_RESOLVING_FAILED
-    MessageBox MB_ICONEXCLAMATION '$1:$\r$\nexit code resolving failed'
-    ; fill me
+    MessageBox MB_ICONEXCLAMATION '$2:$\r$\n>> exit code resolving failed <<$\r$\n"unspecified exit code"$\r$\n$3'
   ${Break}
 
   ${Case} 5 # EXIT_BINARY_NOT_FOUND
-    MessageBox MB_ICONEXCLAMATION '$1:$\r$\nbinary not found'
-    ; fill me
+    MessageBox MB_ICONEXCLAMATION '$2:$\r$\n>> binary not found <<$\r$\n"Will be returned if a referenced binary was not found"$\r$\n$3'
   ${Break}
 
   ${Case} 6 # EXIT_CONFIG_NOT_FOUND
-    MessageBox MB_ICONEXCLAMATION '$1:$\r$\nconfig not found'
-    ; fill me
+    MessageBox MB_ICONEXCLAMATION '$2:$\r$\n>> config not found <<$\r$\n"Will be returned if no valid configuration was found"$\r$\n$3'
   ${Break}
 
   ${Case} 10 # EXIT_UPGRADE_FAILED
-    MessageBox MB_ICONEXCLAMATION '$1:$\r$\nupgrade failed'
-    ; Will be returned when the database upgrade failed
+    MessageBox MB_ICONEXCLAMATION '$2:$\r$\n>> upgrade failed <<$\r$\n"Will be returned when the database upgrade failed"$\r$\n$3'
   ${Break}
 
   ${Case} 11 # EXIT_UPGRADE_REQUIRED
-    MessageBox MB_ICONEXCLAMATION '$1:$\r$\ndb upgrade required'
-    ; Will be returned when a database upgrade is required
+    MessageBox MB_ICONEXCLAMATION '$2:$\r$\n>> db upgrade required <<$\r$\n"Will be returned when a database upgrade is required"$\r$\n$3'
   ${Break}
 
   ${Case} 12 # EXIT_DOWNGRADE_REQUIRED
-    MessageBox MB_ICONEXCLAMATION '$1:$\r$\ndb downgrade required'
-    ; Will be returned when a database upgrade is required
+    MessageBox MB_ICONEXCLAMATION '$2:$\r$\n>> db downgrade required <<$\r$\n"Will be returned when a database upgrade is required"$\r$\n$3'
   ${Break}
 
   ${Case} 13 # EXIT_VERSION_CHECK_FAILED
-    MessageBox MB_ICONEXCLAMATION '$1:$\r$\nversion check failed'
-    ; Will be returned when there is a version mismatch
+    MessageBox MB_ICONEXCLAMATION '$2:$\r$\n>> version check failed <<$\r$\n"Will be returned when there is a version mismatch"$\r$\n$3'
   ${Break}
 
   ${Case} 20 # EXIT_ALREADY_RUNNING
-    MessageBox MB_ICONEXCLAMATION '$1:$\r$\nalready running'
-    ; Will be returned when arangod is already running according to PID-file
+    MessageBox MB_ICONEXCLAMATION '$2:$\r$\n>> already running <<$\r$\n"Will be returned when arangod is already running according to PID-file"$\r$\n$3'
   ${Break}
 
   ${Case} 21 # EXIT_COULD_NOT_BIND_PORT
-    MessageBox MB_ICONEXCLAMATION '$1:$\r$\nport blocked'
-    ; Will be returned when endpoint is taken by another process
+    MessageBox MB_ICONEXCLAMATION '$2:$\r$\n>> port blocked <<$\r$\n"Will be returned when the configured tcp endpoint is already occupied by another process"$\r$\n$3'
   ${Break}
 
   ${Case} 22 # EXIT_COULD_NOT_LOCK
-    MessageBox MB_ICONEXCLAMATION '$1:$\r$\ncould not lock - another process could be running'
-    ; fill me
+    MessageBox MB_ICONEXCLAMATION '$2:$\r$\n>> could not lock - another process could be running <<$\r$\n"Will be returned if another ArangoDB process is running, or the state can not be cleared"$\r$\n$3'
   ${Break}
 
   ${Case} 23 # EXIT_RECOVERY
-    MessageBox MB_ICONEXCLAMATION '$1:$\r$\nrecovery failed'
+    MessageBox MB_ICONEXCLAMATION '$2:$\r$\n>> recovery failed <<$\r$\n"Will be returned if the automatic database startup recovery fails"$\r$\n$3'
+  ${Break}
+
+  ${Case} 24 # EXIT_DB_NOT_EMPTY
+    MessageBox MB_ICONEXCLAMATION '$2:$\r$\n>> database not empty <<$\r$\n"Will be returned when commanding to initialize a non empty directory as database"$\r$\n$3'
+  ${Break}
+
+  ${Default}
+    MessageBox MB_ICONEXCLAMATION '$2:$\r$\nUnknown exit code $1!'
     ; Will be returned if the recovery fails
   ${Break}
 
diff --git a/Installation/Windows/Plugins/xcopy.nsh b/Installation/Windows/Plugins/xcopy.nsh
new file mode 100644
index 0000000000..7826b80122
--- /dev/null
+++ b/Installation/Windows/Plugins/xcopy.nsh
@@ -0,0 +1,32 @@
+!macro xCopyDir sourceDir DestDir
+  push ${sourceDir}
+  push ${DestDir}
+call xCopyDir
+!macroend
+Function xCopyDir
+  pop $4
+  pop $3
+  ReadEnvStr $5 COMSPEC
+
+  FindFirst $0 $1 "$3\*"
+    loop:
+      StrCmp $1 "" done
+      StrCmp $1 "." skip
+      StrCmp $1 ".." skip
+
+      IfFileExists "$3\$1\*.*" IsDir 0
+      DetailPrint "File Source: $3\$1"
+      DetailPrint "Dest: $4"
+      ExecWait '$5 /C xcopy /E /C /H /K /O /Y "$3\$1" "$4\" '
+      goto skip
+  IsDir:
+      DetailPrint "Dir Source: $3\$1"
+      DetailPrint "Dest: $4"
+      ExecWait '$5 /C xcopy /E /C /H /K /O /Y "$3\$1" "$4\$1\" '
+  skip:
+    FindNext $0 $1
+      Goto loop
+    done:
+  FindClose $0
+
+FunctionEnd
diff --git a/Installation/Windows/Templates/NSIS.template.in b/Installation/Windows/Templates/NSIS.template.in
index dbde28dc5e..1863ea1723 100755
--- a/Installation/Windows/Templates/NSIS.template.in
+++ b/Installation/Windows/Templates/NSIS.template.in
@@ -14,6 +14,7 @@
   !include "WinMessages.nsh"
   !include "MUI2.nsh"
   !include "StripSlashes.nsh"
+  !include "xcopy.nsh"
 ;   !include "GetTime.nsh"
 ;--------------------------------
 ; get commandline parameters
@@ -56,13 +57,13 @@ Var ADD_TO_PATH               ; x bool
 Var AUTOMATIC_UPDATE
 Var AUTOMATIC_BACKUP
 
+# determine_possible_install_scope sets:
 Var AllowGlobalInstall
 
 Var ChooseInstallPath
 
 Var BackupPath
 
-
 VAR TRI_INSTALL_SERVICE       ; x bool
 VAR TRI_INSTALL_SCOPE_ALL     ; x bool => All / ThisUser
 Var newCfgValues              ; keep new config file values
@@ -72,11 +73,11 @@ Var ServiceUp                 ; did the service start?
 
 Var DATADIR
 Var APPDIR
-Var LOGFILE
+; Var LOGFILE
 
 Var ini_DATADIR
 Var ini_APPDIR
-Var ini_LOGFILE
+; Var ini_LOGFILE
 
 Var UpgradeInstall
 Var LaunchAfterInstall
@@ -124,6 +125,17 @@ RequestExecutionLevel highest
 !include "WaitForService.nsh"
 !include "ReadINIFileKeys.nsh"
 
+!macro determine_possible_install_scope
+    UserInfo::GetAccountType
+    pop $0
+    ${If} $0 == "admin"
+      StrCpy $AllowGlobalInstall "1"
+    ${Else}
+      StrCpy $AllowGlobalInstall "0"
+    ${EndIf}
+!macroend
+
+
 !macro determine_install_scope un
   Function ${un}determine_install_scope
     Pop $0
@@ -210,11 +222,6 @@ OldFound:
   StrCpy $UpgradeInstall "1"
 FunctionEnd
 
-Function disableBackButton
-     GetDlgItem $0 $HWNDParent 3
-     EnableWindow $0 0
-FunctionEnd
-
 Function stop_old_service
   ${If} $TRI_INSTALL_SERVICE == 1
      SimpleSC::StopService    '${TRI_SVC_NAME}' 0 30
@@ -498,7 +505,6 @@ Function InstallOptionsPage1
 continueUI:
   !insertmacro determineInstallScope 1
   Push ${TEMP1}
-displayAgain:
 
   !insertmacro MUI_HEADER_TEXT "Install Options" "Choose options for installing @CPACK_NSIS_PACKAGE_NAME@"
 
@@ -715,36 +721,34 @@ FunctionEnd
 
 Function UpgradeExisting
   ; Check whether we acutally should upgrade:
+  !insertmacro StripBackslash DATADIR
+  !insertmacro StripSlash DATADIR      
   DetailPrint "Checking whether an existing database needs upgrade: "
   ExecWait "$INSTDIR\${SBIN_DIR}\arangod.exe --server.rest-server false --log.foreground-tty false --database.check-version" $0
   DetailPrint "done Checking whether an existing database needs upgrade: $0"
   ${If} $0 != 0
-  ${AndIf} $0 != 11
-    !insertmacro printExitCode $0 "failed to detect whether we need to Upgrade"
-  ${ElseIf} $0 == 11
+  ${AndIf} $0 != ${ARANGO_EXIT_UPGRADE_REQUIRED}
+    !insertmacro printExitCode $0 "failed to detect whether we need to Upgrade" ""
+  ${ElseIf} $0 == ${ARANGO_EXIT_UPGRADE_REQUIRED}
   ${AndIf} $AUTOMATIC_UPDATE == "1"
-    DetailPrint "Yes."
+    DetailPrint "Update required."
 
     ${If} $AUTOMATIC_BACKUP == "1"
       ; We should and we should keep a backup:
       StrCpy $BackupPath "$DATADIR"
-      !insertmacro StripBackslash BackupPath
-      !insertmacro StripSlash BackupPath      
       ${GetTime} "" "L" $0 $1 $2 $3 $4 $5 $6
       StrCpy $BackupPath "$BackupPath_$2-$1-$0_$4_$5_$6"
       CreateDirectory "$BackupPath"
-      ClearErrors
-      DetailPrint "Copying old database from $DATADIR to backup directory $BackupPath"
-      CopyFiles "$DATADIR" "$BackupPath"
-      IfErrors 0 +2
-      MessageBox MB_ICONEXCLAMATION "The upgrade failed to copy the files $\r$\nfrom '$DATADIR'$\r$\nto '$BackupPath'; please do it manually.$\r$\n$\r$\nClick OK to continue."
+      DetailPrint "Copying old database from $DATADIR"
+      DetailPrint "to backup directory $BackupPath"
+      !insertmacro xCopyDir "$DATADIR" "$BackupPath"
     ${EndIf}
     DetailPrint "Attempting to run database upgrade: "
     ; Now actually do the upgrade
     ExecWait "$INSTDIR\${SBIN_DIR}\arangod.exe --server.rest-server false  --log.level error --database.auto-upgrade true" $0
     DetailPrint "Done running database upgrade: $0"
     ${If} $0 != 0
-      !insertmacro printExitCode $0 "the Upgrade failed, please do a manual upgrade"
+      !insertmacro printExitCode $0 "the Upgrade failed, please do a manual upgrade" ""
       Abort
     ${EndIf}
   ${EndIf}
@@ -761,7 +765,7 @@ Function SetDBPassword
   ${If} $0 == 0
     return
   ${Else}
-    !insertmacro printExitCode $0 "Failed to initialize database password.$\r$\nPlease check the Windows event log for more details$\r$\n"
+    !insertmacro printExitCode $0 "Failed to initialize database password$\r$\n" "Please check the Windows event log for more details$\r$\n"
     Abort
   ${EndIf}
   error:
@@ -792,8 +796,9 @@ Function InstallService
          ${If} $2 == "1"
            MessageBox MB_OK "${SC_WAITED}$\r$\nbut it exited with an error; $\r$\n${SC_SV}$\r$\n${SC_EVLOG}"
            Abort
-         ${ElseIf} $2 == "2"
-           MessageBox MB_OK "${SC_WAITED}$\r$\nbut it exited with a fatal error; $\r$\n${SC_SV}$\r$\n${SC_EVLOG}"
+         ${Else}
+           !insertmacro printExitCode $2 "${SC_WAITED}$\r$\nbut it exited with a fatal error" "$\r$\n${SC_SV}$\r$\n${SC_EVLOG};$\r$\nExit status: $2"
+           ; MessageBox MB_OK "${SC_WAITED}$\r$\nbut it exited with a fatal error; $\r$\n${SC_SV}$\r$\n${SC_EVLOG}"
            Abort
          ${EndIf}
        ${ElseIf} $1 != "0"
@@ -928,9 +933,9 @@ Section "-Core installation"
   ${If} $APPDIR != ""
     StrCpy $ini_APPDIR "[javascript]$\r$\napp-path = $APPDIR$\r$\n"
   ${EndIf}
-  ${If} $LOGFILE != ""
-    StrCpy $ini_LOGFILE "[log]$\r$\nfile = $LOGFILE$\r$\n"
-  ${EndIf}
+  ;${If} $LOGFILE != ""
+  ;  StrCpy $ini_LOGFILE "[log]$\r$\nfile = $LOGFILE$\r$\n"
+  ;${EndIf}
   StrCpy $newCfgValues "$ini_APPDIR$ini_DATADIR[server]$\r$\nstorage-engine = $STORAGE_ENGINE$\r$\n"
   StrCpy $newCfgValuesFile "$INSTDIR\etc\arangodb3\newValues.ini"
   FileOpen $4  "$newCfgValuesFile" w
@@ -1021,13 +1026,8 @@ FunctionEnd
 ;--------------------------------
 ; determine admin versus local install
 Function un.onInit
-  UserInfo::GetAccountType
-  pop $0
-  ${If} $0 == "admin"
-    StrCpy $AllowGlobalInstall "1"
-  ${Else}
-    StrCpy $AllowGlobalInstall "0"
-  ${EndIf}
+  ; are we allowed to un.install admin in first place?
+  !insertmacro determine_possible_install_scope
 
 ; ArangoDB may be installed in different places
 ; Determine if the ArangoDB was installed for a local user
@@ -1227,18 +1227,11 @@ SectionEnd
 ; Choose different default installation folder based on SV_ALLUSERS...
 ; "Program Files" for AllUsers, "My Documents" for JustMe...
 
-var allPathOpts
 var CMDINSTDIR
 
 Function .onInit
-  UserInfo::GetAccountType
-  pop $0
-  ${If} $0 == "admin"
-    StrCpy $AllowGlobalInstall "1"
-  ${Else}
-    StrCpy $AllowGlobalInstall "0"
-  ${EndIf}
-
+  ; are we allowed to install admin in first place?
+  !insertmacro determine_possible_install_scope
   ${GetParameters} $R0
   ClearErrors
   ${GetOptions} $R0 "/INSTALL_SCOPE_ALL=" $0
diff --git a/arangod/RestServer/InitDatabaseFeature.cpp b/arangod/RestServer/InitDatabaseFeature.cpp
index 495ee9fcb6..82687a7cfe 100644
--- a/arangod/RestServer/InitDatabaseFeature.cpp
+++ b/arangod/RestServer/InitDatabaseFeature.cpp
@@ -26,6 +26,7 @@
 #include <iostream>
 #include <thread>
 
+#include "Basics/exitcodes.h"
 #include "Basics/FileUtils.h"
 #include "Basics/terminal-utils.h"
 #include "Cluster/ServerState.h"
@@ -151,7 +152,7 @@ void InitDatabaseFeature::checkEmptyDatabase() {
 
   bool empty = false;
   std::string message;
-  int code = 2;
+  int code = TRI_EXIT_CODE_RESOLVING_FAILED;
 
   if (FileUtils::exists(path)) {
     if (!FileUtils::isDirectory(path)) {
@@ -176,6 +177,7 @@ void InitDatabaseFeature::checkEmptyDatabase() {
 
   if (!empty) {
     message = "database already initialized, refusing to initialize it again";
+    code = TRI_EXIT_DB_NOT_EMPTY;
     goto doexit;
   }
 
diff --git a/cmake/packages/nsis.cmake b/cmake/packages/nsis.cmake
index 084d554f23..1510c2b39a 100644
--- a/cmake/packages/nsis.cmake
+++ b/cmake/packages/nsis.cmake
@@ -8,6 +8,7 @@ set(CPACK_NSIS_MODIFY_PATH         ON)
 set(CPACK_NSIS_ENABLE_UNINSTALL_BEFORE_INSTALL 1)
 set(CPACK_MODULE_PATH "${CMAKE_CURRENT_SOURCE_DIR}/Installation/Windows/Templates")
 set(CPACK_PLUGIN_PATH "${CMAKE_CURRENT_SOURCE_DIR}/Installation/Windows/Plugins")
+set(CPACK_PACKAGE_INSTALL_REGISTRY_KEY "${CPACK_PACKAGE_NAME} ${CPACK_PACKAGE_VERSION}-${ARANGODB_PACKAGE_REVISION}_${ARANGODB_PACKAGE_ARCHITECTURE}")
 # want @ in @only nsis template:
 set(CPACK_ROOTDIR "@ROOTDIR@")
 if (CMAKE_CL_64)
diff --git a/lib/ApplicationFeatures/WindowsServiceFeature.cpp b/lib/ApplicationFeatures/WindowsServiceFeature.cpp
index e6f0b01b25..f80b397b12 100644
--- a/lib/ApplicationFeatures/WindowsServiceFeature.cpp
+++ b/lib/ApplicationFeatures/WindowsServiceFeature.cpp
@@ -453,9 +453,9 @@ void WindowsServiceFeature::shutDownFailure () {
 /// @brief wrap ArangoDB server so we can properly emmit a status on shutdown
 ///        starting
 //////////////////////////////////////////////////////////////////////////////
-void WindowsServiceFeature::abortFailure () {
+void WindowsServiceFeature::abortFailure (uint16_t exitCode) {
   // startup finished - signalize we're running.
-  SetServiceStatus(SERVICE_STOP, ERROR_SERVICE_SPECIFIC_ERROR, 0, 0, 2);
+  SetServiceStatus(SERVICE_STOP, ERROR_SERVICE_SPECIFIC_ERROR, 0, 0, exitCode);
 }
 
 ////////////////////////////////////////////////////////////////////////////////
@@ -549,10 +549,10 @@ void WindowsServiceFeature::collectOptions(std::shared_ptr<ProgramOptions> optio
                            new BooleanParameter(&_stopWaitService));
 }
 
-void WindowsServiceFeature::abortService() {
+void WindowsServiceFeature::abortService(uint16_t exitCode) {
   if (ArangoInstance != nullptr) {
     ArangoInstance->_server = nullptr;
-    ArangoInstance->abortFailure();
+    ArangoInstance->abortFailure(exitCode);
   }
   exit(EXIT_FAILURE);
 }
diff --git a/lib/ApplicationFeatures/WindowsServiceFeature.h b/lib/ApplicationFeatures/WindowsServiceFeature.h
index 5756ea3a71..52bda88f04 100644
--- a/lib/ApplicationFeatures/WindowsServiceFeature.h
+++ b/lib/ApplicationFeatures/WindowsServiceFeature.h
@@ -54,8 +54,8 @@ class WindowsServiceFeature final : public application_features::ApplicationFeat
   void shutDownBegins ();
   void shutDownComplete ();
   void shutDownFailure ();
-  void abortFailure();
-  static void abortService();
+  void abortFailure(uint16_t exitCode);
+  static void abortService(uint16_t exitCode);
 
  public:
   bool _installService = false;
diff --git a/lib/Basics/exitcodes.cpp b/lib/Basics/exitcodes.cpp
index 287131c2f9..52b32c7ac7 100644
--- a/lib/Basics/exitcodes.cpp
+++ b/lib/Basics/exitcodes.cpp
@@ -20,4 +20,5 @@ void TRI_InitializeExitMessages() {
   REG_EXIT(EXIT_COULD_NOT_BIND_PORT, "port blocked");
   REG_EXIT(EXIT_COULD_NOT_LOCK, "could not lock - another process could be running");
   REG_EXIT(EXIT_RECOVERY, "recovery failed");
+  REG_EXIT(EXIT_DB_NOT_EMPTY, "database not empty");
 }
diff --git a/lib/Basics/exitcodes.dat b/lib/Basics/exitcodes.dat
index b9227a8017..bd820fe12a 100755
--- a/lib/Basics/exitcodes.dat
+++ b/lib/Basics/exitcodes.dat
@@ -5,10 +5,10 @@
 # general
 EXIT_SUCCESS,0,"success","No error has occurred."
 EXIT_FAILED,1,"exit with error","Will be returned when a general error occurred."
-EXIT_CODE_RESOLVING_FAILED,2,"exit code resolving failed","fill me"
+EXIT_CODE_RESOLVING_FAILED,2,"exit code resolving failed","unspecified exit code"
 
-EXIT_BINARY_NOT_FOUND,5,"binary not found","fill me"
-EXIT_CONFIG_NOT_FOUND,6,"config not found","fill me"
+EXIT_BINARY_NOT_FOUND,5,"binary not found","Will be returned if a referenced binary was not found"
+EXIT_CONFIG_NOT_FOUND,6,"config not found","Will be returned if no valid configuration was found"
 
 # internal
 EXIT_UPGRADE_FAILED,10,"upgrade failed","Will be returned when the database upgrade failed"
@@ -18,11 +18,12 @@ EXIT_VERSION_CHECK_FAILED,13,"version check failed","Will be returned when there
 
 # startup
 EXIT_ALREADY_RUNNING,20,"already running","Will be returned when arangod is already running according to PID-file"
-EXIT_COULD_NOT_BIND_PORT,21,"port blocked","Will be returned when endpoint is taken by another process"
-EXIT_COULD_NOT_LOCK,22,"could not lock - another process could be running","fill me"
-EXIT_RECOVERY,23,"recovery failed","Will be returned if the recovery fails"
+EXIT_COULD_NOT_BIND_PORT,21,"port blocked","Will be returned when the configured tcp endpoint is already occupied by another process"
+EXIT_COULD_NOT_LOCK,22,"could not lock - another process could be running","Will be returned if another ArangoDB process is running, or the state can not be cleared"
+EXIT_RECOVERY,23,"recovery failed","Will be returned if the automatic database startup recovery fails"
+EXIT_DB_NOT_EMPTY,24,"database not empty","Will be returned when commanding to initialize a non empty directory as database"
 
 # network
 #EXIT_NO_COORDINATOR
 #EXIT_NO_AGENCY
-#EXIT_NO_CONNECTIVITY
+#EXIT_NO_CONNECTIVITY
\ No newline at end of file
diff --git a/lib/Basics/exitcodes.h b/lib/Basics/exitcodes.h
index ef8d5c64c7..afa6241f0e 100644
--- a/lib/Basics/exitcodes.h
+++ b/lib/Basics/exitcodes.h
@@ -18,17 +18,17 @@ constexpr int TRI_EXIT_FAILED
 
 /// 2: EXIT_CODE_RESOLVING_FAILED
 /// exit code resolving failed
-/// fill me
+/// unspecified exit code
 constexpr int TRI_EXIT_CODE_RESOLVING_FAILED                                    = 2;
 
 /// 5: EXIT_BINARY_NOT_FOUND
 /// binary not found
-/// fill me
+/// Will be returned if a referenced binary was not found
 constexpr int TRI_EXIT_BINARY_NOT_FOUND                                         = 5;
 
 /// 6: EXIT_CONFIG_NOT_FOUND
 /// config not found
-/// fill me
+/// Will be returned if no valid configuration was found
 constexpr int TRI_EXIT_CONFIG_NOT_FOUND                                         = 6;
 
 /// 10: EXIT_UPGRADE_FAILED
@@ -58,19 +58,27 @@ constexpr int TRI_EXIT_ALREADY_RUNNING
 
 /// 21: EXIT_COULD_NOT_BIND_PORT
 /// port blocked
-/// Will be returned when endpoint is taken by another process
+/// Will be returned when the configured tcp endpoint is already occupied by
+/// another process
 constexpr int TRI_EXIT_COULD_NOT_BIND_PORT                                      = 21;
 
 /// 22: EXIT_COULD_NOT_LOCK
 /// could not lock - another process could be running
-/// fill me
+/// Will be returned if another ArangoDB process is running, or the state can
+/// not be cleared
 constexpr int TRI_EXIT_COULD_NOT_LOCK                                           = 22;
 
 /// 23: EXIT_RECOVERY
 /// recovery failed
-/// Will be returned if the recovery fails
+/// Will be returned if the automatic database startup recovery fails
 constexpr int TRI_EXIT_RECOVERY                                                 = 23;
 
+/// 24: EXIT_DB_NOT_EMPTY
+/// database not empty
+/// Will be returned when commanding to initialize a non empty directory as
+/// database
+constexpr int TRI_EXIT_DB_NOT_EMPTY                                             = 24;
+
 
 /// register all exit codes for ArangoDB
 void TRI_InitializeExitMessages();
diff --git a/lib/Basics/win-utils.cpp b/lib/Basics/win-utils.cpp
index 2ecda7fb6c..0ab30f6b64 100644
--- a/lib/Basics/win-utils.cpp
+++ b/lib/Basics/win-utils.cpp
@@ -526,7 +526,7 @@ void TRI_SetWindowsServiceAbortFunction(TRI_serviceAbort_t f) {
 
 void ADB_WindowsExitFunction(int exitCode, void* data) {
   if (serviceAbort != nullptr) {
-    serviceAbort();
+    serviceAbort(exitCode);
   }
 
   exit(exitCode);
diff --git a/lib/Basics/win-utils.h b/lib/Basics/win-utils.h
index 29e39d4768..98cdd131ae 100644
--- a/lib/Basics/win-utils.h
+++ b/lib/Basics/win-utils.h
@@ -83,7 +83,7 @@ int TRI_MapSystemError(DWORD);
 bool TRI_InitWindowsEventLog(void);
 void TRI_CloseWindowsEventlog(void);
 
-typedef void (*TRI_serviceAbort_t)(void);
+typedef void (*TRI_serviceAbort_t)(uint16_t exitCode);
 
 void TRI_SetWindowsServiceAbortFunction(TRI_serviceAbort_t);
 
diff --git a/utils/generateExitCodesFiles.py b/utils/generateExitCodesFiles.py
index 20809abc36..4eea51f77f 100755
--- a/utils/generateExitCodesFiles.py
+++ b/utils/generateExitCodesFiles.py
@@ -59,22 +59,32 @@ def genNSISFile(errors, filename):
 
   impl = """
 !include "LogicLib.nsh"
-!macro printExitCode exitCode Message
+"""
+  for e in errors:
+    impl += """!define ARANGO_%s %s
+""" % (
+  e[0],
+  e[1]
+  )
+
+  impl +="""
+!macro printExitCode exitCode Message DetailMessage
   Push "${exitCode}"
   Push "${Message}"
+  Push "${DetailMessage}"
   Call printExitCode
 !macroend
 Function printExitCode
-pop $1
+pop $3
 pop $2
-${Switch} $0\n
+pop $1
+${Switch} $1\n
 """
   # print individual errors
   for e in errors:
     impl += """
   ${Case} %s # %s
-    MessageBox MB_ICONEXCLAMATION '$1:$\\r$\\n%s'
-    ; %s
+    MessageBox MB_ICONEXCLAMATION '$2:$\\r$\\n>> %s <<$\\r$\\n"%s"$\\r$\\n$3'
   ${Break}
 """ % (
   e[1],
@@ -84,6 +94,11 @@ ${Switch} $0\n
   )
 
   impl = impl + """
+  ${Default}
+    MessageBox MB_ICONEXCLAMATION '$2:$\\r$\\nUnknown exit code $1!'
+    ; Will be returned if the recovery fails
+  ${Break}
+
 ${EndSwitch}
 FunctionEnd
 """