diff --git a/appveyor.yml b/appveyor.yml
index 426a9e7..8b2d9df 100644
--- a/appveyor.yml
+++ b/appveyor.yml
@@ -84,11 +84,15 @@ environment:
     APPVEYOR_BUILD_WORKER_IMAGE: macos-monterey
     HOMEBREW_NO_INSTALL_CLEANUP: 1
     CC: clang
+    CFLAGS: "-I/usr/local/include -I/usr/local/opt/openssl/include"
+    LDFLAGS: "-L/usr/local/lib -L/usr/local/opt/openssl/lib"
     CONFIGURE_OPTIONS: ""
   - TARGET: macos-x64-gcc
     BUILD_ENVIRONMENT: xcode
     APPVEYOR_BUILD_WORKER_IMAGE: macos-monterey
     HOMEBREW_NO_INSTALL_CLEANUP: 1
+    CFLAGS: "-I/usr/local/include -I/usr/local/opt/openssl/include"
+    LDFLAGS: "-L/usr/local/lib -L/usr/local/opt/openssl/lib"
     CONFIGURE_OPTIONS: ""
   - TARGET: macos-x64-gcc-python
     BUILD_ENVIRONMENT: xcode
@@ -96,8 +100,8 @@ environment:
     PYTHON: "/usr/local/opt/python@3.11/bin/python3"
     PYTHON_CONFIG: "/usr/local/opt/python@3.11/bin/python3-config"
     HOMEBREW_NO_INSTALL_CLEANUP: 1
-    CFLAGS: "-I/usr/local/include"
-    LDFLAGS: "-L/usr/local/lib"
+    CFLAGS: "-I/usr/local/include -I/usr/local/opt/openssl/include"
+    LDFLAGS: "-L/usr/local/lib -L/usr/local/opt/openssl/lib"
     CONFIGURE_OPTIONS: "--enable-python"
   - TARGET: macos-pkgbuild
     BUILD_ENVIRONMENT: xcode
@@ -105,8 +109,8 @@ environment:
     PYTHON: "/usr/local/opt/python@3.11/bin/python3"
     PYTHON_CONFIG: "/usr/local/opt/python@3.11/bin/python3-config"
     HOMEBREW_NO_INSTALL_CLEANUP: 1
-    CFLAGS: "-I/usr/local/include"
-    LDFLAGS: "-L/usr/local/lib"
+    CFLAGS: "-I/usr/local/include -I/usr/local/opt/openssl/include"
+    LDFLAGS: "-L/usr/local/lib -L/usr/local/opt/openssl/lib"
     CONFIGURE_OPTIONS: "--disable-dependency-tracking --prefix=/usr/local --enable-python --with-pyprefix"
   - TARGET: python311
     BUILD_ENVIRONMENT: python
diff --git a/tests/test_md5sum.sh b/tests/test_md5sum.sh
index ef5e2ee..dcdf30e 100755
--- a/tests/test_md5sum.sh
+++ b/tests/test_md5sum.sh
@@ -153,6 +153,11 @@ do
 		fi
 		for INPUT_FILE in "${INPUT_FILES[@]}";
 		do
+			if test "${OSTYPE}" = "msys";
+			then
+				# A test executable built with MinGW expects a Windows path.
+				INPUT_FILE=`echo ${INPUT_FILE} | sed 's?/?\\\\?g'`;
+			fi
 			TESTED_WITH_OPTIONS=0;
 
 			for OPTION_SET in ${OPTION_SETS[@]};
diff --git a/tests/test_sha1sum.sh b/tests/test_sha1sum.sh
index a4791bc..1105fb6 100755
--- a/tests/test_sha1sum.sh
+++ b/tests/test_sha1sum.sh
@@ -153,6 +153,11 @@ do
 		fi
 		for INPUT_FILE in "${INPUT_FILES[@]}";
 		do
+			if test "${OSTYPE}" = "msys";
+			then
+				# A test executable built with MinGW expects a Windows path.
+				INPUT_FILE=`echo ${INPUT_FILE} | sed 's?/?\\\\?g'`;
+			fi
 			TESTED_WITH_OPTIONS=0;
 
 			for OPTION_SET in ${OPTION_SETS[@]};
diff --git a/tests/test_sha2sum.sh b/tests/test_sha2sum.sh
index 59d2933..247bea4 100755
--- a/tests/test_sha2sum.sh
+++ b/tests/test_sha2sum.sh
@@ -187,6 +187,11 @@ do
 		fi
 		for INPUT_FILE in "${INPUT_FILES[@]}";
 		do
+			if test "${OSTYPE}" = "msys";
+			then
+				# A test executable built with MinGW expects a Windows path.
+				INPUT_FILE=`echo ${INPUT_FILE} | sed 's?/?\\\\?g'`;
+			fi
 			TESTED_WITH_OPTIONS=0;
 
 			for OPTION_SET in ${OPTION_SETS[@]};