diff --git a/Makefile b/Makefile
index 1da0ce7..0f97693 100644
--- a/Makefile
+++ b/Makefile
@@ -20,6 +20,13 @@ OPTFLAGS += -DSETPROCTITLE -DSPT_TYPE=2
 # System dependant blocks... if your system is listed below, uncomment
 # the relevant lines
 
+# MSYS
+# The current version of gcc from MSYS defines __MSYS__ and __CYGWIN__.
+# To avoid to change the code, simply define CYGWIN additionally. 
+ifneq ($(filter $(MSYSTEM),MSYS MINGW32 MINGW64 UCRT64),)
+CFLAGS += -DCYGWIN
+endif
+
 # OpenBSD
 #OPTFLAGS += -DHAVE_SYS_PSTAT_H
 
diff --git a/buildwin.sh b/buildwin.sh
index 52d8b59..5e1165c 100644
--- a/buildwin.sh
+++ b/buildwin.sh
@@ -4,13 +4,13 @@ echo "Build docs..."
 make -C docs
 
 echo "Build proxytunnel..."
-make -f Makefile.ssl11
-
-echo "Copy msys/openssl dll to build dir..."
-cp  /usr/bin/msys-2.0.dll /usr/bin/msys-crypto-1.1.dll /usr/bin/msys-ssl-1.1.dll /usr/bin/msys-z.dll .
+make -f Makefile
+strip -s proxytunnel.exe
 
 echo "Generate proxytunnel.zip with docs, exe and msys/openssl dll..."
-zip proxytunnel.zip proxytunnel.exe *.dll docs/proxytunnel.1 docs/proxytunnel.1.html docs/proxytunnel-paper.html
+zip proxytunnel.zip proxytunnel.exe docs/proxytunnel.1 docs/proxytunnel.1.html docs/proxytunnel-paper.html
+DLLS="$(ldd proxytunnel.exe | grep msys.*\.dll | awk '{print $3}' | xargs) /usr/lib/ossl-modules/legacy.dll"
+zip proxytunnel.zip -j $DLLS 
 
 if [ ! -z "${TRAVIS_TAG}" ]; then 
 echo "Deploy proxytunnel.zip to github release tag:${TRAVIS_TAG}..."
diff --git a/ntlm.c b/ntlm.c
index 54761f5..5159202 100644
--- a/ntlm.c
+++ b/ntlm.c
@@ -29,6 +29,9 @@
 #include <ctype.h>
 #include <sys/time.h>
 #if OPENSSL_VERSION_NUMBER >= 0x30000000L
+	#ifdef CYGWIN
+		#include <unistd.h>
+	#endif
 	#include <openssl/provider.h>
 	#include <openssl/evp.h>
 #else
@@ -71,8 +74,55 @@ unsigned char lm2digest[LM2_DIGEST_LEN];
 
 void init_ntlm() {
 #if OPENSSL_VERSION_NUMBER >= 0x30000000L
-	OSSL_PROVIDER_load(NULL, "default");
-	OSSL_PROVIDER_load(NULL, "legacy");
+	OSSL_PROVIDER *provider;
+	provider = OSSL_PROVIDER_load(NULL, "default");
+	if (!provider) {
+		my_perror("Loading default provider failed");
+		exit(1);
+	}
+	provider = OSSL_PROVIDER_load(NULL, "legacy");
+#ifdef CYGWIN
+	if (!provider) {
+		// available at msys and git for windows
+		// the msys version has an additional dependency on libcrypto-3-x64.dll
+		provider = OSSL_PROVIDER_load(NULL, "/mingw64/lib/ossl-modules/legacy.dll");
+	}
+	if (!provider) {
+		// available at msys (without dependency on libcrypto-3-x64.dll)
+		provider = OSSL_PROVIDER_load(NULL, "/usr/lib/ossl-modules/legacy.dll");
+	}
+	if (!provider) {
+		// default installation path for additional tools
+		provider = OSSL_PROVIDER_load(NULL, "/usr/local/bin/legacy.dll");
+	}
+	if (!provider) {
+		// directory of proxytunnel itself
+		const char *p = strrchr(program_name, '/');
+		if (p) {
+			const int len = p - program_name;
+			char *tmp = (char*)alloca(len + sizeof("/legacy.dll"));
+			memcpy(tmp, program_name, len);
+			strcpy(tmp + len, "/legacy.dll");
+			provider = OSSL_PROVIDER_load(NULL, tmp);
+		}
+	}
+	if (!provider) {
+		// current working directory
+		char *cwd = getcwd(NULL, 0);
+		if (cwd) {
+			const int len = strlen(cwd);
+			char *tmp = (char*)alloca(len + sizeof("/legacy.dll"));
+			memcpy(tmp, cwd, len);
+			free(cwd);
+			strcpy(tmp + len, "/legacy.dll");
+			provider = OSSL_PROVIDER_load(NULL, tmp);
+		}
+	}	
+#endif
+	if (!provider) {
+		my_perror("Loading legacy provider failed");
+		exit(1);
+	}
 	md4alg = EVP_md4();
 	md5alg = EVP_md5();
 	mdctx = EVP_MD_CTX_new();