diff --git a/toolkit/components/maintenanceservice/Makefile.in b/toolkit/components/maintenanceservice/Makefile.in
index 7b7c5d30dc9e..524e54542bb5 100644
--- a/toolkit/components/maintenanceservice/Makefile.in
+++ b/toolkit/components/maintenanceservice/Makefile.in
@@ -64,7 +64,6 @@ MOZ_GLUE_PROGRAM_LDFLAGS =
 
 LIBS += \
   ../../mozapps/update/common/$(LIB_PREFIX)updatecommon.$(LIB_SUFFIX) \
-  ../../mozapps/readstrings/$(LIB_PREFIX)readstrings.$(LIB_SUFFIX) \
   $(NULL)
 
 USE_STATIC_LIBS = 1
@@ -98,5 +97,4 @@ endif
 # Pick up nsWindowsRestart.cpp
 LOCAL_INCLUDES += -I$(topsrcdir)/toolkit/xre \
   -I$(topsrcdir)/toolkit/mozapps/update/common \
-  -I$(topsrcdir)/toolkit/mozapps/readstrings \
   $(NULL)
diff --git a/toolkit/components/maintenanceservice/workmonitor.cpp b/toolkit/components/maintenanceservice/workmonitor.cpp
index f5efb257d1d5..3ad4dab16843 100644
--- a/toolkit/components/maintenanceservice/workmonitor.cpp
+++ b/toolkit/components/maintenanceservice/workmonitor.cpp
@@ -56,6 +56,7 @@
 #include "registrycertificates.h"
 #include "uachelper.h"
 #include "updatehelper.h"
+#include "errors.h"
 
 // Wait 15 minutes for an update operation to run at most.
 // Updates usually take less than a minute so this seems like a 
@@ -66,16 +67,6 @@ BOOL WriteStatusFailure(LPCWSTR updateDirPath, int errorCode);
 BOOL PathGetSiblingFilePath(LPWSTR destinationBuffer,  LPCWSTR siblingFilePath, 
                             LPCWSTR newFileName);
 
-// The error codes start from 16000 since Windows system error 
-// codes only go up to 15999
-const int SERVICE_UPDATER_COULD_NOT_BE_STARTED = 16000;
-const int SERVICE_NOT_ENOUGH_COMMAND_LINE_ARGS = 16001;
-const int SERVICE_UPDATER_SIGN_ERROR = 16002;
-const int SERVICE_UPDATER_COMPARE_ERROR = 16003;
-const int SERVICE_UPDATER_IDENTITY_ERROR = 16004;
-const int SERVICE_STILL_APPLYING_ON_SUCCESS = 16005;
-const int SERVICE_STILL_APPLYING_ON_FAILURE = 16006;
-
 /* 
  * Read the update.status file and sets isApplying to true if
  * the status is set to applying
diff --git a/toolkit/mozapps/readstrings/Makefile.in b/toolkit/mozapps/readstrings/Makefile.in
deleted file mode 100644
index 8a69fb33cd85..000000000000
--- a/toolkit/mozapps/readstrings/Makefile.in
+++ /dev/null
@@ -1,54 +0,0 @@
-# ***** BEGIN LICENSE BLOCK *****
-# Version: MPL 1.1/GPL 2.0/LGPL 2.1
-#
-# The contents of this file are subject to the Mozilla Public License Version
-# 1.1 (the "License"); you may not use this file except in compliance with
-# the License. You may obtain a copy of the License at
-# http://www.mozilla.org/MPL/
-#
-# Software distributed under the License is distributed on an "AS IS" basis,
-# WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
-# for the specific language governing rights and limitations under the
-# License.
-#
-# The Original Code is Mozilla readstrings
-#
-# The Initial Developer of the Original Code is The Mozilla Foundation.
-#
-# Portions created by the Initial Developer are Copyright (C) 2009
-# the Mozilla Foundation <http://www.mozilla.org/>. All Rights Reserved.
-#
-# Contributor(s): 
-#   Brad Lassey <blassey@mozilla.com> (original author)
-#
-# Alternatively, the contents of this file may be used under the terms of
-# either the GNU General Public License Version 2 or later (the "GPL"), or
-# the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
-# in which case the provisions of the GPL or the LGPL are applicable instead
-# of those above. If you wish to allow use of your version of this file only
-# under the terms of either the GPL or the LGPL, and not to allow others to
-# use your version of this file under the terms of the MPL, indicate your
-# decision by deleting the provisions above and replace them with the notice
-# and other provisions required by the GPL or the LGPL. If you do not delete
-# the provisions above, a recipient may use your version of this file under
-# the terms of any one of the MPL, the GPL or the LGPL.
-#
-# ***** END LICENSE BLOCK *****
-
-DEPTH     = ../../..
-topsrcdir = @top_srcdir@
-srcdir    = @srcdir@
-VPATH     = @srcdir@
-
-include $(DEPTH)/config/autoconf.mk
-
-MODULE  = readstrings
-LIBRARY_NAME = readstrings
-FORCE_STATIC_LIB = 1
-export NO_SHUNT = 1
-USE_STATIC_LIBS = 1
-
-CPPSRCS = readstrings.cpp
-EXPORTS = readstrings.h
-
-include $(topsrcdir)/config/rules.mk
diff --git a/toolkit/mozapps/update/Makefile.in b/toolkit/mozapps/update/Makefile.in
index 752647bbad05..432046a9b40a 100644
--- a/toolkit/mozapps/update/Makefile.in
+++ b/toolkit/mozapps/update/Makefile.in
@@ -49,8 +49,6 @@ XPIDLSRCS = nsIUpdateTimerManager.idl
 EXTRA_PP_COMPONENTS = nsUpdateTimerManager.js nsUpdateTimerManager.manifest
 
 ifdef MOZ_UPDATER
-DIRS = ../readstrings
-
 ifneq ($(OS_TARGET),Android)
 DIRS += common
 DIRS += updater
@@ -70,7 +68,6 @@ else
 # used for other things.  We need to build update/common
 # which the maintenance service uses.
 ifdef MOZ_MAINTENANCE_SERVICE
-DIRS = ../readstrings
 ifneq ($(OS_TARGET),Android)
 DIRS += common
 endif
diff --git a/toolkit/mozapps/update/common/Makefile.in b/toolkit/mozapps/update/common/Makefile.in
index d7b91bbc5aa8..242b7a5ec9d9 100644
--- a/toolkit/mozapps/update/common/Makefile.in
+++ b/toolkit/mozapps/update/common/Makefile.in
@@ -52,10 +52,12 @@ endif
 
 CPPSRCS = \
   updatelogging.cpp \
+  readstrings.cpp \
   $(NULL)
 
 EXPORTS = updatelogging.h \
   updatedefines.h \
+  readstrings.h \
   $(NULL)
 
 ifeq ($(MOZ_WIDGET_TOOLKIT),windows)
diff --git a/toolkit/mozapps/readstrings/errors.h b/toolkit/mozapps/update/common/errors.h
similarity index 82%
rename from toolkit/mozapps/readstrings/errors.h
rename to toolkit/mozapps/update/common/errors.h
index 7a156b42053d..9fc8e7ed6642 100644
--- a/toolkit/mozapps/readstrings/errors.h
+++ b/toolkit/mozapps/update/common/errors.h
@@ -40,8 +40,12 @@
 #define Errors_h__
 
 #define OK 0
-//#define MEM_ERROR 1  // Replaced with errors 10-16 (inclusive)
+
+// Old unused error codes:
+// #define MEM_ERROR 1  // Replaced with errors 10-16 (inclusive)
 // #define IO_ERROR 2  // Use READ_ERROR or WRITE_ERROR instead
+
+// Error codes 3-16 are for general update problems.
 #define USAGE_ERROR 3
 #define CRC_ERROR 4
 #define PARSE_ERROR 5
@@ -56,6 +60,9 @@
 #define UPDATER_QUOTED_PATH_MEM_ERROR 14
 #define BAD_ACTION_ERROR 15
 #define STRING_CONVERSION_ERROR 16
+
+// Error codes 17-23 are related to security tasks for MAR
+// signing and MAR protection.
 #define CERT_LOAD_ERROR 17
 #define CERT_HANDLING_ERROR 18
 #define CERT_VERIFY_ERROR 19
@@ -64,6 +71,16 @@
 #define MAR_CHANNEL_MISMATCH_ERROR 22
 #define VERSION_DOWNGRADE_ERROR 23
 
+// Error codes 24-30 are related to the maintenance service
+// and so are Windows only
+#define SERVICE_UPDATER_COULD_NOT_BE_STARTED 24
+#define SERVICE_NOT_ENOUGH_COMMAND_LINE_ARGS 25
+#define SERVICE_UPDATER_SIGN_ERROR 26
+#define SERVICE_UPDATER_COMPARE_ERROR 27
+#define SERVICE_UPDATER_IDENTITY_ERROR 28
+#define SERVICE_STILL_APPLYING_ON_SUCCESS 29
+#define SERVICE_STILL_APPLYING_ON_FAILURE 30
+
 // The following error codes are only used by updater.exe
 // when a fallback key exists and XPCShell tests are being run.
 #define FALLBACKKEY_UNKNOWN_ERROR 100
diff --git a/toolkit/mozapps/readstrings/readstrings.cpp b/toolkit/mozapps/update/common/readstrings.cpp
similarity index 100%
rename from toolkit/mozapps/readstrings/readstrings.cpp
rename to toolkit/mozapps/update/common/readstrings.cpp
diff --git a/toolkit/mozapps/readstrings/readstrings.h b/toolkit/mozapps/update/common/readstrings.h
similarity index 100%
rename from toolkit/mozapps/readstrings/readstrings.h
rename to toolkit/mozapps/update/common/readstrings.h
diff --git a/toolkit/mozapps/update/nsUpdateService.js b/toolkit/mozapps/update/nsUpdateService.js
index 2e57bea7a333..bd8b5fa2d9e6 100644
--- a/toolkit/mozapps/update/nsUpdateService.js
+++ b/toolkit/mozapps/update/nsUpdateService.js
@@ -143,13 +143,13 @@ const UNEXPECTED_ERROR   = 8;
 const ELEVATION_CANCELED = 9;
 
 // Windows service specific errors
-const SERVICE_UPDATER_COULD_NOT_BE_STARTED = 16000;
-const SERVICE_NOT_ENOUGH_COMMAND_LINE_ARGS = 16001;
-const SERVICE_UPDATER_SIGN_ERROR           = 16002;
-const SERVICE_UPDATER_COMPARE_ERROR        = 16003;
-const SERVICE_UPDATER_IDENTITY_ERROR       = 16004;
-const SERVICE_STILL_APPLYING_ON_SUCCESS    = 16005;
-const SERVICE_STILL_APPLYING_ON_FAILURE    = 16006;
+const SERVICE_UPDATER_COULD_NOT_BE_STARTED = 24;
+const SERVICE_NOT_ENOUGH_COMMAND_LINE_ARGS = 25;
+const SERVICE_UPDATER_SIGN_ERROR           = 26;
+const SERVICE_UPDATER_COMPARE_ERROR        = 27;
+const SERVICE_UPDATER_IDENTITY_ERROR       = 28;
+const SERVICE_STILL_APPLYING_ON_SUCCESS    = 29;
+const SERVICE_STILL_APPLYING_ON_FAILURE    = 30;
 
 const CERT_ATTR_CHECK_FAILED_NO_UPDATE  = 100;
 const CERT_ATTR_CHECK_FAILED_HAS_UPDATE = 101;
diff --git a/toolkit/mozapps/update/test/Makefile.in b/toolkit/mozapps/update/test/Makefile.in
index 6fefd7761215..17ceb9499ecd 100644
--- a/toolkit/mozapps/update/test/Makefile.in
+++ b/toolkit/mozapps/update/test/Makefile.in
@@ -84,7 +84,7 @@ LOCAL_INCLUDES += \
 MOZ_WINCONSOLE = 1
 
 LIBS += \
-  ../../readstrings/$(LIB_PREFIX)readstrings.$(LIB_SUFFIX) \
+  ../common/$(LIB_PREFIX)updatecommon.$(LIB_SUFFIX) \
   $(NULL)
 
 ifeq ($(OS_ARCH),WINNT)
diff --git a/toolkit/mozapps/update/test/TestAUSHelper.cpp b/toolkit/mozapps/update/test/TestAUSHelper.cpp
index 5a0983388758..e6405a777cc8 100644
--- a/toolkit/mozapps/update/test/TestAUSHelper.cpp
+++ b/toolkit/mozapps/update/test/TestAUSHelper.cpp
@@ -31,6 +31,9 @@
 # define NS_ttoi _wtoi
 # define NS_tstat _wstat
 # define LOG_S "%S"
+
+#include "../common/updatehelper.h"
+
 #else
 # include <unistd.h>
 # define NS_main main
@@ -153,214 +156,6 @@ VerifyCertificateTrustForFile(LPCWSTR filePath)
   return WinVerifyTrust(NULL, &policyGUID, &trustData);
 }
 
-/**
- * Waits for a service to enter a stopped state.
- * This function does not stop the service, it just blocks until the service
- * is stopped.
- *
- * @param  serviceName     The service to wait for.
- * @param  maxWaitSeconds  The maximum number of seconds to wait
- * @return state of the service after a timeout or when stopped.
- *         A value of 255 is returned for an error. Typical values are:
- *         SERVICE_STOPPED 0x00000001
- *         SERVICE_START_PENDING 0x00000002
- *         SERVICE_STOP_PENDING 0x00000003
- *         SERVICE_RUNNING 0x00000004
- *         SERVICE_CONTINUE_PENDING 0x00000005
- *         SERVICE_PAUSE_PENDING 0x00000006
- *         SERVICE_PAUSED 0x00000007
- *         last status not set 0x000000CF
- *         Could no query status 0x000000DF
- *         Could not open service, access denied 0x000000EB
- *         Could not open service, invalid handle 0x000000EC
- *         Could not open service, invalid name 0x000000ED
- *         Could not open service, does not exist 0x000000EE
- *         Could not open service, other error 0x000000EF
- *         Could not open SCM, access denied 0x000000FD
- *         Could not open SCM, database does not exist 0x000000FE;
- *         Could not open SCM, other error 0x000000FF;
- * Note: The strange choice of error codes above SERVICE_PAUSED are chosen
- * in case Windows comes out with other service stats higher than 7, they
- * would likely call it 8 and above.  JS code that uses this in TestAUSHelper
- * only handles values up to 255 so that's why we don't use GetLastError 
- * directly.
- */
-DWORD
-WaitForServiceStop(LPCWSTR serviceName, DWORD maxWaitSeconds)
-{
-  // 0x000000CF is defined above to be not set
-  DWORD lastServiceState = 0x000000CF;
-
-  // Get a handle to the SCM database.
-  SC_HANDLE serviceManager = OpenSCManager(NULL, NULL, 
-                                           SC_MANAGER_CONNECT | 
-                                           SC_MANAGER_ENUMERATE_SERVICE);
-  if (!serviceManager)  {
-    DWORD lastError = GetLastError();
-    switch(lastError) {
-    case ERROR_ACCESS_DENIED:
-      return 0x000000FD;
-    case ERROR_DATABASE_DOES_NOT_EXIST:
-      return 0x000000FE;
-    default:
-      return 0x000000FF;
-    }
-  }
-
-  // Get a handle to the service.
-  SC_HANDLE service = OpenServiceW(serviceManager, 
-                                   serviceName, 
-                                   SERVICE_QUERY_STATUS);
-  if (!service) {
-    DWORD lastError = GetLastError();
-    CloseServiceHandle(serviceManager);
-    switch(lastError) {
-    case ERROR_ACCESS_DENIED:
-      return 0x000000EB;
-    case ERROR_INVALID_HANDLE:
-      return 0x000000EC;
-    case ERROR_INVALID_NAME:
-      return 0x000000ED;
-    // If the service does not exist, keep trying in case it does exist soon.
-    // I think there might be an issue with the TALOS machines and some of 
-    // the machines having an old maintenanceservice.exe that used to 
-    // uninstall when upgrading.  Those should already be upgraded but this 
-    // is safer.
-    case ERROR_SERVICE_DOES_NOT_EXIST:
-      if (maxWaitSeconds == 0) {
-        return 0x000000EE;
-      } else {
-        Sleep(1000);
-        return WaitForServiceStop(serviceName, maxWaitSeconds - 1);
-      }
-    default:
-      return 0x000000EF;
-    } 
-  }
-
-  DWORD currentWaitMS = 0;
-  SERVICE_STATUS_PROCESS ssp;
-  ssp.dwCurrentState = lastServiceState;
-  while (currentWaitMS < maxWaitSeconds * 1000) {
-    DWORD bytesNeeded;
-    if (!QueryServiceStatusEx(service, SC_STATUS_PROCESS_INFO, (LPBYTE)&ssp,
-                              sizeof(SERVICE_STATUS_PROCESS), &bytesNeeded)) {
-      DWORD lastError = GetLastError();
-      switch (lastError) {
-      case ERROR_INVALID_HANDLE:
-        ssp.dwCurrentState = 0x000000D9;
-        break;
-      case ERROR_ACCESS_DENIED:
-        ssp.dwCurrentState = 0x000000DA;
-        break;
-      case ERROR_INSUFFICIENT_BUFFER:
-        ssp.dwCurrentState = 0x000000DB;
-        break;
-      case ERROR_INVALID_PARAMETER:
-        ssp.dwCurrentState = 0x000000DC;
-        break;
-      case ERROR_INVALID_LEVEL:
-        ssp.dwCurrentState = 0x000000DD;
-        break;
-      case ERROR_SHUTDOWN_IN_PROGRESS:
-        ssp.dwCurrentState = 0x000000DE;
-        break;
-      // These 3 errors can occur when the service is not yet stopped but
-      // it is stopping.
-      case ERROR_INVALID_SERVICE_CONTROL:
-      case ERROR_SERVICE_CANNOT_ACCEPT_CTRL:
-      case ERROR_SERVICE_NOT_ACTIVE:
-        currentWaitMS += 50;
-        Sleep(50);
-        continue;
-      default:
-        ssp.dwCurrentState = 0x000000DF;
-      }
-
-      // We couldn't query the status so just break out
-      break;
-    }
-
-    // The service is already in use.
-    if (ssp.dwCurrentState == SERVICE_STOPPED) {
-      break;
-    }
-    currentWaitMS += 50;
-    Sleep(50);
-  }
-
-  lastServiceState = ssp.dwCurrentState;
-  CloseServiceHandle(service);
-  CloseServiceHandle(serviceManager);
-  return lastServiceState;
-}
-
-/**
- * Determines if there is at least one process running for the specified
- * application. A match will be found across any session for any user.
- *
- * @param process The process to check for existance
- * @return ERROR_NOT_FOUND if the process was not found
- * @       ERROR_SUCCESS if the process was found and there were no errors
- * @       Other Win32 system error code for other errors
-**/
-DWORD
-IsProcessRunning(LPCWSTR filename)
-{
-  // Take a snapshot of all processes in the system.
-  HANDLE snapshot = CreateToolhelp32Snapshot(TH32CS_SNAPPROCESS, 0);
-  if (INVALID_HANDLE_VALUE == snapshot) {
-    return GetLastError();
-  }
-  
-  PROCESSENTRY32W processEntry;
-  processEntry.dwSize = sizeof(PROCESSENTRY32W);
-  if (!Process32FirstW(snapshot, &processEntry)) {
-    DWORD lastError = GetLastError();
-    CloseHandle(snapshot);
-    return lastError;
-  }
-
-  do {
-    if (wcsicmp(filename, processEntry.szExeFile) == 0) {
-      CloseHandle(snapshot);
-      return ERROR_SUCCESS;
-    }
-  } while (Process32NextW(snapshot, &processEntry));
-  CloseHandle(snapshot);
-  return ERROR_NOT_FOUND;
-}
-
-/**
- * Waits for the specified applicaiton to exit.
- *
- * @param filename   The application to wait for.
- * @param maxSeconds The maximum amount of seconds to wait for all
- *                   instances of the application to exit.
- * @return  ERROR_SUCCESS if no instances of the application exist
- *          WAIT_TIMEOUT if the process is still running after maxSeconds.
- *          Any other Win32 system error code.
-*/
-DWORD
-WaitForProcessExit(LPCWSTR filename, DWORD maxSeconds)
-{
-  DWORD applicationRunningError = WAIT_TIMEOUT;
-  for(DWORD i = 0; i < maxSeconds; i++) {
-    DWORD applicationRunningError = IsProcessRunning(filename);
-    if (ERROR_NOT_FOUND == applicationRunningError) {
-      return ERROR_SUCCESS;
-    }
-    Sleep(1000);
-  }
-
-  if (ERROR_SUCCESS == applicationRunningError) {
-    return WAIT_TIMEOUT;
-  }
-
-  return applicationRunningError;
-}
-
-
 #endif
 
 int NS_main(int argc, NS_tchar **argv)
diff --git a/toolkit/mozapps/update/test/TestAUSReadStrings.cpp b/toolkit/mozapps/update/test/TestAUSReadStrings.cpp
index 335cc228695c..77cfeb51e6f1 100644
--- a/toolkit/mozapps/update/test/TestAUSReadStrings.cpp
+++ b/toolkit/mozapps/update/test/TestAUSReadStrings.cpp
@@ -65,8 +65,8 @@
 
 #include "updater/resource.h"
 #include "updater/progressui.h"
-#include "../../readstrings/readstrings.h"
-#include "../../readstrings/errors.h"
+#include "common/readstrings.h"
+#include "common/errors.h"
 
 #ifndef MAXPATHLEN
 # ifdef PATH_MAX
diff --git a/toolkit/mozapps/update/updater/Makefile.in b/toolkit/mozapps/update/updater/Makefile.in
index d7321f5bf385..990ff477e11e 100644
--- a/toolkit/mozapps/update/updater/Makefile.in
+++ b/toolkit/mozapps/update/updater/Makefile.in
@@ -55,13 +55,13 @@ PROGRAM = updater$(BIN_SUFFIX)
 MOZ_GLUE_LDFLAGS =
 MOZ_GLUE_PROGRAM_LDFLAGS =
 
-LOCAL_INCLUDES += -I$(srcdir)/../../readstrings \
-  -I$(srcdir)/../common
+LOCAL_INCLUDES += \
+  -I$(srcdir)/../common \
+  $(NULL)
 
 LIBS += \
   ../common/$(LIB_PREFIX)updatecommon.$(LIB_SUFFIX) \
   $(DEPTH)/modules/libmar/src/$(LIB_PREFIX)mar.$(LIB_SUFFIX) \
-  ../../readstrings/$(LIB_PREFIX)readstrings.$(LIB_SUFFIX) \
   $(BZ2_LIBS) \
   $(NULL)
 
diff --git a/toolkit/toolkit-makefiles.sh b/toolkit/toolkit-makefiles.sh
index 6c91aa5633b9..f3d3138e70fb 100644
--- a/toolkit/toolkit-makefiles.sh
+++ b/toolkit/toolkit-makefiles.sh
@@ -1377,17 +1377,6 @@ if [ "$MOZ_UPDATER" ]; then
   fi
 fi
 
-if [ "$MOZ_UPDATER" -o "$MOZ_MAINTENANCE_SERVICE" ]; then
-  add_makefiles "
-    toolkit/mozapps/readstrings/Makefile
-  "
-  if [ "$OS_TARGET" != "Android" ]; then
-    add_makefiles "
-      toolkit/mozapps/update/common/Makefile
-    "
-  fi
-fi
-
 if [ "$MOZ_UPDATER" -o "$MOZ_UPDATE_PACKAGING" ]; then
   add_makefiles "
     other-licenses/bsdiff/Makefile