diff --git a/Docs/src/misc.but b/Docs/src/misc.but
index 4aab15da..b1a99c60 100644
--- a/Docs/src/misc.but
+++ b/Docs/src/misc.but
@@ -1,5 +1,11 @@
 \S1{miscinst} Miscellaneous Instructions
 
+\S2{geterrorlevel} GetErrorLevel
+
+\c user_var(error level output)
+
+Returns the last error level set by \R{seterrorlevel}{SetErrorLevel} or -1 if it was never used.
+
 \S2{getinstdirerror} GetInstDirError
 
 \c user_var(error output)
@@ -16,6 +22,12 @@ Use in the leave function of a directory page. Reads the flag set if '\R{adirver
 
 Initializes the plugins dir (\R{varconstant}{$PLUGINSDIR}) if not already initialized.
 
+\S2{seterrorlevel} SetErrorLevel
+
+\c error_level
+
+Sets the error level of the installer or uninstaller to \e{error_level}. See \R{errorlevels}{Error Levels} for more information.
+
 \S2{setshellvarcontext} SetShellVarContext
 
 \c \\<b\\>current\\</b\\>|all
diff --git a/Docs/src/usefulinfos.but b/Docs/src/usefulinfos.but
index d8a8f819..769e64f9 100644
--- a/Docs/src/usefulinfos.but
+++ b/Docs/src/usefulinfos.but
@@ -20,21 +20,15 @@ When building with precompiled exehead .h files, you should set the USE_PRECOMPI
 
 Like other applications installers made by NSIS return error levels as a result of their execution. Checking the error level can be useful if you call an NSIS installer from another application or installer.
 
-Normal installers:
-
 \b 0 - Normal execution (no error)
 
-\b 1 - Installation aborted by user
+\b 1 - Installation aborted by user (cancel button)
 
 \b 2 - Installation aborted by script
 
-Silent installers:
+As of NSIS 2.01, you can set the error level to other values using \R{seterrorlevel}{SetErrorLevel}.
 
-\b 0 - Normal execution (no error)
-
-\b 1 - Installation aborted by user
-
-\b 1 - Installation aborted by script
+All of the above information applies both to installers and uninstallers.
 
 \H{useful_add_uninst_infos}Add uninstall information to Add/Remove Programs
 
diff --git a/Source/exehead/Main.c b/Source/exehead/Main.c
index 2012ad09..d2fbb256 100644
--- a/Source/exehead/Main.c
+++ b/Source/exehead/Main.c
@@ -70,7 +70,7 @@ char *ValidateTempDir()
 
 int WINAPI WinMain(HINSTANCE hInstance, HINSTANCE hPrevInst,LPSTR lpszCmdParam, int nCmdShow)
 {
-  static int ret;
+  int ret;
   const char *m_Err = _LANG_ERRORWRITINGTEMP;
 
   int cl_flags = 0;
@@ -81,6 +81,8 @@ int WINAPI WinMain(HINSTANCE hInstance, HINSTANCE hPrevInst,LPSTR lpszCmdParam,
 
   InitCommonControls();
 
+  g_exec_flags.errlvl=-1;
+
 #if defined(NSIS_SUPPORT_ACTIVEXREG) || defined(NSIS_SUPPORT_CREATESHORTCUT)
   {
     extern HRESULT g_hres;
@@ -243,6 +245,8 @@ int WINAPI WinMain(HINSTANCE hInstance, HINSTANCE hPrevInst,LPSTR lpszCmdParam,
 #endif//NSIS_CONFIG_UNINSTALL_SUPPORT
 
   ret = ui_doinstall();
+  if (g_exec_flags.errlvl == -1)
+    g_exec_flags.errlvl = ret;
 
 #ifdef NSIS_CONFIG_LOG
 #ifndef NSIS_CONFIG_LOG_ODS
@@ -254,13 +258,16 @@ end:
   CleanUp();
 
   if (m_Err)
+  {
     my_MessageBox(m_Err, MB_OK | MB_ICONSTOP | (IDOK << 20));
+    g_exec_flags.errlvl = 2;
+  }
 
 #if defined(NSIS_SUPPORT_ACTIVEXREG) || defined(NSIS_SUPPORT_CREATESHORTCUT)
   OleUninitialize();
 #endif
 
-  ExitProcess(ret);
+  ExitProcess(g_exec_flags.errlvl);
 }
 
 void NSISCALL CleanUp()
diff --git a/Source/exehead/Ui.c b/Source/exehead/Ui.c
index e9d242ae..737ee16a 100644
--- a/Source/exehead/Ui.c
+++ b/Source/exehead/Ui.c
@@ -302,7 +302,7 @@ FORCE_INLINE int NSISCALL ui_doinstall(void)
 
 #ifdef NSIS_SUPPORT_CODECALLBACKS
   // Select language
-  if (ExecuteCallbackFunction(CB_ONINIT)) return 1;
+  if (ExecuteCallbackFunction(CB_ONINIT)) return 2;
   set_language();
 #endif
 
@@ -363,7 +363,7 @@ FORCE_INLINE int NSISCALL ui_doinstall(void)
 #ifdef NSIS_SUPPORT_CODECALLBACKS
       if (!g_quit_flag) ExecuteCallbackFunction(CB_ONINSTFAILED);
 #endif//NSIS_SUPPORT_CODECALLBACKS
-      return 1;
+      return 2;
     }
 #ifdef NSIS_SUPPORT_CODECALLBACKS
     ExecuteCallbackFunction(CB_ONINSTSUCCESS);
@@ -1596,7 +1596,7 @@ static BOOL CALLBACK InstProc(HWND hwndDlg, UINT uMsg, WPARAM wParam, LPARAM lPa
   {
     if (g_quit_flag)
     {
-      m_retcode=1;
+      m_retcode=2;
       outernotify(NOTIFY_BYE_BYE);
     }
     else
diff --git a/Source/exehead/fileform.h b/Source/exehead/fileform.h
index f09c35de..08d117f3 100644
--- a/Source/exehead/fileform.h
+++ b/Source/exehead/fileform.h
@@ -467,6 +467,7 @@ typedef struct
 #endif
   int instdir_error;
   int rtl;
+  int errlvl;
 } exec_flags;
 
 #define FIELDN(x, y) (((int *)&x)[y])
diff --git a/Source/script.cpp b/Source/script.cpp
index 3c9f218c..ad92190a 100644
--- a/Source/script.cpp
+++ b/Source/script.cpp
@@ -4280,6 +4280,19 @@ int CEXEBuild::doCommand(int which_token, LineParser &line)
       ent.offsets[1]=add_intstring(1);
       SCRIPT_MSG("SetErrors\n");
     return add_entry(&ent);
+    case TOK_SETERRORLEVEL:
+      ent.which=EW_SETFLAG;
+      ent.offsets[0]=FLAG_OFFSET(errlvl);
+      ent.offsets[1]=add_string(line.gettoken_str(1));
+      SCRIPT_MSG("SetErrorLevel: %s\n",line.gettoken_str(1));
+    return add_entry(&ent);
+    case TOK_GETERRORLEVEL:
+      ent.which=EW_GETFLAG;
+      ent.offsets[0]=GetUserVarIndex(line, 1);
+      ent.offsets[1]=FLAG_OFFSET(errlvl);
+      if (line.gettoken_str(1)[0] && ent.offsets[0]<0) PRINTHELP()
+      SCRIPT_MSG("GetErrorLevel: %s\n",line.gettoken_str(1));
+    return add_entry(&ent);
 #ifdef NSIS_SUPPORT_STROPTS
     case TOK_STRLEN:
       ent.which=EW_STRLEN;
diff --git a/Source/tokens.cpp b/Source/tokens.cpp
index 02ea07f7..9b311ea4 100644
--- a/Source/tokens.cpp
+++ b/Source/tokens.cpp
@@ -177,6 +177,8 @@ static tokenType tokenlist[TOK__LAST] =
 {TOK_SETDETAILSVIEW,"SetDetailsView",1,0,"(hide|show)",TP_CODE},
 {TOK_SETDETAILSPRINT,"SetDetailsPrint",1,0,"(none|listonly|textonly|both)",TP_CODE},
 {TOK_SETERRORS,"SetErrors",0,0,"",TP_CODE},
+{TOK_SETERRORLEVEL,"SetErrorLevel",1,0,"error_level",TP_CODE},
+{TOK_GETERRORLEVEL,"GetErrorLevel",1,0,"$(user_var: output)",TP_CODE},
 {TOK_SETFILEATTRIBUTES,"SetFileAttributes",2,0,"file attribute[|attribute[...]]\n    attribute=(NORMAL|ARCHIVE|HIDDEN|OFFLINE|READONLY|SYSTEM|TEMPORARY|0)",TP_CODE},
 {TOK_SETFONT,"SetFont",2,1,"[/LANG=lang_id] font_face_name font_size",TP_GLOBAL},
 {TOK_SETOUTPATH,"SetOutPath",1,0,"output_path",TP_CODE},
diff --git a/Source/tokens.h b/Source/tokens.h
index 29abb830..4442c132 100644
--- a/Source/tokens.h
+++ b/Source/tokens.h
@@ -237,6 +237,8 @@ enum
   TOK_ENABLEWINDOW,
   TOK_SETSILENT,
   TOK_IFSILENT,
+  TOK_SETERRORLEVEL,
+  TOK_GETERRORLEVEL,
   TOK_LOCKWINDOW,
 
   TOK__LAST,