diff --git a/src/testdir/Make_dos.mak b/src/testdir/Make_dos.mak
index 4809930..3073e9e 100644
--- a/src/testdir/Make_dos.mak
+++ b/src/testdir/Make_dos.mak
@@ -38,7 +38,7 @@
 $(DOSTMP_INFILES): $(*B).in
 	if not exist $(DOSTMP)\NUL md $(DOSTMP)
 	if exist $@ del $@
-	$(VIMPROG) -u dos.vim --noplugin "+set ff=dos|f $@|wq" $(*B).in
+	$(VIMPROG) -u dos.vim -U NONE --noplugin "+set ff=dos|f $@|wq" $(*B).in
 
 # For each input file dostmp/test99.in run the tests.
 # This moves test99.in to test99.in.bak temporarily.
@@ -55,7 +55,7 @@
 	-@if exist Xfind rd /s /q Xfind
 	-@del X*
 	-@if exist viminfo del viminfo
-	$(VIMPROG) -u dos.vim --noplugin "+set ff=unix|f test.out|wq" \
+	$(VIMPROG) -u dos.vim -U NONE --noplugin "+set ff=unix|f test.out|wq" \
 		$(DOSTMP)\$(*B).out
 	@diff test.out $*.ok & if errorlevel 1 \
 		( move /y test.out $*.failed \
@@ -114,4 +114,4 @@
 newtests: $(NEW_TESTS)
 
 .vim.res:
-	$(VIMPROG) -u NONE -S runtest.vim $*.vim
+	$(VIMPROG) -u NONE -U NONE -S runtest.vim $*.vim