diff --git a/appveyor.yml b/appveyor.yml
index 46edf5fb..b946ea06 100644
--- a/appveyor.yml
+++ b/appveyor.yml
@@ -90,6 +90,7 @@ build_script:
   - ps: >-
       if (!($env:Configuration -Like "*Light*")) {
           cd C:\zlib
+          (Get-Content win32/Makefile.msc).replace('-MD', '-MT') | Set-Content win32/Makefile.msc
           If ($env:Platform -Match "x86") {
              nmake -f win32/Makefile.msc LOC="-DASMV -DASMINF" OBJA="inffas32.obj match686.obj" zlib.lib
           } Else {