diff --git a/config/config.mk b/config/config.mk
index 8196e62414..d15336939f 100644
--- a/config/config.mk
+++ b/config/config.mk
@@ -756,15 +756,11 @@ endif
 ifdef NSINSTALL_BIN
 NSINSTALL	= $(CYGWIN_WRAPPER) $(NSINSTALL_BIN)
 else
-ifeq (WINNT,$(CROSS_COMPILE)$(OS_ARCH))
-NSINSTALL	= $(CYGWIN_WRAPPER) $(MOZ_TOOLS_DIR)/bin/nsinstall
-else
 ifeq (OS2,$(CROSS_COMPILE)$(OS_ARCH))
 NSINSTALL	= $(MOZ_TOOLS_DIR)/nsinstall
 else
 NSINSTALL	= $(CONFIG_TOOLS)/nsinstall
 endif # OS2
-endif # WINNT
 endif # NSINSTALL_BIN
 
 
diff --git a/config/rules.mk b/config/rules.mk
index 8549311943..98dea88e4f 100644
--- a/config/rules.mk
+++ b/config/rules.mk
@@ -127,8 +127,8 @@ endif
 testxpcobjdir = $(MOZDEPTH)/_tests/xpcshell
 
 # Test file installation
-ifdef NSINSTALL_BIN
-# nsinstall in moztools can't recursively copy directories, so use nsinstall.py
+ifneq (,$(filter WINNT os2-emx,$(HOST_OS_ARCH)))
+# Windows and OS/2 nsinstall can't recursively copy directories, so use nsinstall.py
 TEST_INSTALLER = $(PYTHON) $(MOZILLA_SRCDIR)/config/nsinstall.py
 else
 TEST_INSTALLER = $(INSTALL)
diff --git a/configure.in b/configure.in
index 1ef2ba8b93..0bf4540d7d 100644
--- a/configure.in
+++ b/configure.in
@@ -861,12 +861,9 @@ if test -z "$PYTHON"; then
     AC_MSG_ERROR([python was not found in \$PATH])
 fi
 
-AC_PATH_PROGS(NSINSTALL_BIN, nsinstall )
 if test -z "$COMPILE_ENVIRONMENT"; then
-if test -z "$NSINSTALL_BIN" || test "$NSINSTALL_BIN" = ":"; then
     NSINSTALL_BIN='$(PYTHON) $(MOZILLA_SRCDIR)/config/nsinstall.py'
 fi
-fi
 AC_SUBST(NSINSTALL_BIN)
 
 AC_PATH_PROG(DOXYGEN, doxygen, :)