diff --git a/.appveyor.yml b/.appveyor.yml
index abc5cbeb38..07ba574f4e 100644
--- a/.appveyor.yml
+++ b/.appveyor.yml
@@ -102,6 +102,18 @@ test_script:
 
 on_finish:
 - ps: >-
+    <# if we failed before install:, these functions won't be defined #>
+    Function Execute-Command ($commandPath)
+    {
+        & $commandPath $args 2>&1
+        if ( $LastExitCode -ne 0 ) {
+            $host.SetShouldExit( $LastExitCode )
+        }
+    }
+    Function Execute-Bash ()
+    {
+        Execute-Command 'c:\msys64\usr\bin\bash' '-e' '-c' $args
+    }
     if ($env:compiler -eq "mingw") {
             <# use the MSYS2 user binaries to archive failures #>
             $oldpath = ${env:Path} -split ';'
diff --git a/changes/bug31884 b/changes/bug31884
new file mode 100644
index 0000000000..ddb6c50d74
--- /dev/null
+++ b/changes/bug31884
@@ -0,0 +1,3 @@
+  o Minor bugfixes (Appveyor CI):
+    - Avoid spurious errors when Appveyor CI fails before the install step.
+      Fixes bug 31884; bugfix on 0.3.4.2-alpha.