diff --git a/Windows/appveyor.yml b/Windows/appveyor.yml
index d4c2fc3..d124661 100644
--- a/Windows/appveyor.yml
+++ b/Windows/appveyor.yml
@@ -2,7 +2,7 @@
 #
 # https://ci.appveyor.com/project/nathan_dunfield/cypari-v7ul8
 
-image: Visual Studio 2019
+image: Visual Studio 2015
 
 branches:
   only:
@@ -18,34 +18,34 @@ environment:
     # A build job will be started for each definition below.
 
     - PYTHON: C:\Python27-x64
-      TOOLCHAIN: C:\mingw-w64\x86_64-8.1.0-posix-seh-rt_v6-rev0\mingw64
+      TOOLCHAIN: C:\mingw-w64\x86_64-6.3.0-posix-seh-rt_v5-rev1\mingw64
 
     - PYTHON: C:\Python27
-      TOOLCHAIN: C:\mingw-w64\i686-8.1.0-posix-dwarf-rt_v6-rev0\mingw32
+      TOOLCHAIN: C:\mingw-w64\i686-6.3.0-posix-dwarf-rt_v5-rev1\mingw32
 
-    - PYTHON: C:\Python36-x64
-      TOOLCHAIN: C:\mingw-w64\x86_64-8.1.0-posix-seh-rt_v6-rev0\mingw64
+    # - PYTHON: C:\Python36-x64
+    #   TOOLCHAIN: C:\mingw-w64\x86_64-8.1.0-posix-seh-rt_v6-rev0\mingw64
 
-    - PYTHON: C:\Python36
-      TOOLCHAIN: C:\mingw-w64\i686-8.1.0-posix-dwarf-rt_v6-rev0\mingw32
+    # - PYTHON: C:\Python36
+    #   TOOLCHAIN: C:\mingw-w64\i686-8.1.0-posix-dwarf-rt_v6-rev0\mingw32
 
-    - PYTHON: C:\Python37-x64
-      TOOLCHAIN: C:\mingw-w64\x86_64-8.1.0-posix-seh-rt_v6-rev0\mingw64
+    # - PYTHON: C:\Python37-x64
+    #   TOOLCHAIN: C:\mingw-w64\x86_64-8.1.0-posix-seh-rt_v6-rev0\mingw64
 
-    - PYTHON: C:\Python37
-      TOOLCHAIN: C:\mingw-w64\i686-8.1.0-posix-dwarf-rt_v6-rev0\mingw32
+    # - PYTHON: C:\Python37
+    #   TOOLCHAIN: C:\mingw-w64\i686-8.1.0-posix-dwarf-rt_v6-rev0\mingw32
 
-    - PYTHON: C:\Python38-x64
-      TOOLCHAIN: C:\mingw-w64\x86_64-8.1.0-posix-seh-rt_v6-rev0\mingw64
+    # - PYTHON: C:\Python38-x64
+    #   TOOLCHAIN: C:\mingw-w64\x86_64-8.1.0-posix-seh-rt_v6-rev0\mingw64
 
-    - PYTHON: C:\Python38
-      TOOLCHAIN: C:\mingw-w64\i686-8.1.0-posix-dwarf-rt_v6-rev0\mingw32
+    # - PYTHON: C:\Python38
+    #   TOOLCHAIN: C:\mingw-w64\i686-8.1.0-posix-dwarf-rt_v6-rev0\mingw32
 
-    - PYTHON: C:\Python39-x64
-      TOOLCHAIN: C:\mingw-w64\x86_64-8.1.0-posix-seh-rt_v6-rev0\mingw64
+    # - PYTHON: C:\Python39-x64
+    #   TOOLCHAIN: C:\mingw-w64\x86_64-8.1.0-posix-seh-rt_v6-rev0\mingw64
 
-    - PYTHON: C:\Python39
-      TOOLCHAIN: C:\mingw-w64\i686-8.1.0-posix-dwarf-rt_v6-rev0\mingw32
+    # - PYTHON: C:\Python39
+    #   TOOLCHAIN: C:\mingw-w64\i686-8.1.0-posix-dwarf-rt_v6-rev0\mingw32
 
 install:
   # Note that you must use the environment variable %PYTHON% to refer to