--- a/tools/update-packaging/Makefile.in
+++ b/tools/update-packaging/Makefile.in
@@ -23,19 +23,16 @@ MAR_BIN	= $(DIST)/host/bin/mar$(HOST_BIN
 MBSDIFF_BIN	= $(DIST)/host/bin/mbsdiff$(HOST_BIN_SUFFIX)
 
 OVERRIDE_DEFAULT_GOAL := full-update
 full-update:: complete-patch
 
 ifeq ($(OS_TARGET), WINNT)
 MOZ_PKG_FORMAT	:= SFX7Z
 UNPACKAGE	= '$(subst $(DIST),$(ABS_DIST),$(INSTALLER_PACKAGE))'
-ifdef AB_CD
-UNPACKAGE	= '$(PACKAGE_BASE_DIR)/$(PACKAGE)'
-endif
 endif
 
 include $(topsrcdir)/config/rules.mk
 include $(topsrcdir)/toolkit/mozapps/installer/signing.mk
 include $(topsrcdir)/toolkit/mozapps/installer/packager.mk
 
 ifdef MOZ_EXTERNAL_SIGNING_FORMAT
 # We can't use sha2signcode on mar files
@@ -47,21 +44,24 @@ ifndef MAR_OLD_FORMAT
 MAR_SIGN_FORMAT=mar_sha384
 else
 MAR_SIGN_FORMAT=mar
 endif
 
 dir-stage := $(call mkdir_deps,$(STAGE_DIR))
 
 complete-patch:: $(dir-stage)
+# unpack the windows installer, unless we're an l10n repack, we just packed this
+ifndef IS_LANGUAGE_REPACK
 ifeq ($(OS_TARGET), WINNT)
 	test -f $(UNPACKAGE)
 	$(RM) -rf '$(PACKAGE_DIR)'
 	cd $(PACKAGE_BASE_DIR) && $(INNER_UNMAKE_PACKAGE)
 endif
+endif
 	MAR=$(MAR_BIN) \
 	MOZ_PRODUCT_VERSION=$(MOZ_APP_VERSION) \
 	  $(srcdir)/make_full_update.sh \
 	  '$(DIST)/$(COMPLETE_MAR)' \
 	  '$(PACKAGE_DIR)'
 ifdef MOZ_SIGN_CMD
 	$(MOZ_SIGN_CMD) -f $(MAR_SIGN_FORMAT) '$(DIST)/$(COMPLETE_MAR)'
 endif