diff --git a/src/MQTTAsync.c b/src/MQTTAsync.c
index 1d652233..6ee7862d 100644
--- a/src/MQTTAsync.c
+++ b/src/MQTTAsync.c
@@ -1982,16 +1982,16 @@ int MQTTAsync_connect(MQTTAsync handle, const MQTTAsync_connectOptions* options)
 	if (m->c->sslopts)
 	{
 		if (m->c->sslopts->trustStore)
-			free(m->c->sslopts->trustStore);
+			free((void*)m->c->sslopts->trustStore);
 		if (m->c->sslopts->keyStore)
-			free(m->c->sslopts->keyStore);
+			free((void*)m->c->sslopts->keyStore);
 		if (m->c->sslopts->privateKey)
-			free(m->c->sslopts->privateKey);
+			free((void*)m->c->sslopts->privateKey);
 		if (m->c->sslopts->privateKeyPassword)
-			free(m->c->sslopts->privateKeyPassword);
+			free((void*)m->c->sslopts->privateKeyPassword);
 		if (m->c->sslopts->enabledCipherSuites)
-			free(m->c->sslopts->enabledCipherSuites);
-		free(m->c->sslopts);
+			free((void*)m->c->sslopts->enabledCipherSuites);
+		free((void*)m->c->sslopts);
 		m->c->sslopts = NULL;
 	}
 
@@ -2000,30 +2000,15 @@ int MQTTAsync_connect(MQTTAsync handle, const MQTTAsync_connectOptions* options)
 		m->c->sslopts = malloc(sizeof(MQTTClient_SSLOptions));
 		memset(m->c->sslopts, '\0', sizeof(MQTTClient_SSLOptions));
 		if (options->ssl->trustStore)
-		{
-			m->c->sslopts->trustStore = malloc(strlen(options->ssl->trustStore) + 1);
-			strcpy(m->c->sslopts->trustStore, options->ssl->trustStore); 
-		}
+			m->c->sslopts->trustStore = MQTTStrdup(options->ssl->trustStore);
 		if (options->ssl->keyStore)
-		{
-			m->c->sslopts->keyStore = malloc(strlen(options->ssl->keyStore) + 1);
-			strcpy(m->c->sslopts->keyStore, options->ssl->keyStore);
-		}
+			m->c->sslopts->keyStore = MQTTStrdup(options->ssl->keyStore);
 		if (options->ssl->privateKey)
-		{
-			m->c->sslopts->privateKey = malloc(strlen(options->ssl->privateKey) + 1);
-			strcpy(m->c->sslopts->privateKey, options->ssl->privateKey);
-		}
+			m->c->sslopts->privateKey = MQTTStrdup(options->ssl->privateKey);
 		if (options->ssl->privateKeyPassword)
-		{
-			m->c->sslopts->privateKeyPassword = malloc(strlen(options->ssl->privateKeyPassword) + 1);
-			strcpy(m->c->sslopts->privateKeyPassword, options->ssl->privateKeyPassword);
-		}
+			m->c->sslopts->privateKeyPassword = MQTTStrdup(options->ssl->privateKeyPassword);
 		if (options->ssl->enabledCipherSuites)
-		{
-			m->c->sslopts->enabledCipherSuites = malloc(strlen(options->ssl->enabledCipherSuites) + 1);
-			strcpy(m->c->sslopts->enabledCipherSuites, options->ssl->enabledCipherSuites);
-		}
+			m->c->sslopts->enabledCipherSuites = MQTTStrdup(options->ssl->enabledCipherSuites);
 		m->c->sslopts->enableServerCertAuth = options->ssl->enableServerCertAuth;
 	}
 #endif
@@ -2138,10 +2123,10 @@ int MQTTAsync_isConnected(MQTTAsync handle)
 }
 
 
-int MQTTAsync_subscribeMany(MQTTAsync handle, size_t count, char* const* topic, int* qos, MQTTAsync_responseOptions* response)
+int MQTTAsync_subscribeMany(MQTTAsync handle, int count, char* const* topic, int* qos, MQTTAsync_responseOptions* response)
 {
 	MQTTAsyncs* m = handle;
-	size_t i = 0;
+	int i = 0;
 	int rc = MQTTASYNC_FAILURE;
 	MQTTAsync_queuedCommand* sub;
 	int msgid = 0;
@@ -2216,10 +2201,10 @@ int MQTTAsync_subscribe(MQTTAsync handle, const char* topic, int qos, MQTTAsync_
 }
 
 
-int MQTTAsync_unsubscribeMany(MQTTAsync handle, size_t count, char* const* topic, MQTTAsync_responseOptions* response)
+int MQTTAsync_unsubscribeMany(MQTTAsync handle, int count, char* const* topic, MQTTAsync_responseOptions* response)
 {
 	MQTTAsyncs* m = handle;
-	size_t i = 0;
+	int i = 0;
 	int rc = SOCKET_ERROR;
 	MQTTAsync_queuedCommand* unsub;
 	int msgid = 0;
@@ -2285,7 +2270,7 @@ int MQTTAsync_unsubscribe(MQTTAsync handle, const char* topic, MQTTAsync_respons
 }
 
 
-int MQTTAsync_send(MQTTAsync handle, const char* destinationName, size_t payloadlen, void* payload,
+int MQTTAsync_send(MQTTAsync handle, const char* destinationName, int payloadlen, void* payload,
 							 int qos, int retained, MQTTAsync_responseOptions* response)
 {
 	int rc = MQTTASYNC_SUCCESS;
diff --git a/src/MQTTAsync.h b/src/MQTTAsync.h
index b377a546..5144db3b 100755
--- a/src/MQTTAsync.h
+++ b/src/MQTTAsync.h
@@ -817,7 +817,7 @@ DLLExport int MQTTAsync_subscribe(MQTTAsync handle, const char* topic, int qos,
   * An error code is returned if there was a problem registering the 
   * subscriptions. 
   */
-DLLExport int MQTTAsync_subscribeMany(MQTTAsync handle, size_t count, char* const* topic, int* qos, MQTTAsync_responseOptions* response); 
+DLLExport int MQTTAsync_subscribeMany(MQTTAsync handle, int count, char* const* topic, int* qos, MQTTAsync_responseOptions* response);
 
 /** 
   * This function attempts to remove an existing subscription made by the 
@@ -845,7 +845,7 @@ DLLExport int MQTTAsync_unsubscribe(MQTTAsync handle, const char* topic, MQTTAsy
   * @return ::MQTTASYNC_SUCCESS if the subscriptions are removed. 
   * An error code is returned if there was a problem removing the subscriptions.
   */
-DLLExport int MQTTAsync_unsubscribeMany(MQTTAsync handle, size_t count, char* const* topic, MQTTAsync_responseOptions* response);
+DLLExport int MQTTAsync_unsubscribeMany(MQTTAsync handle, int count, char* const* topic, MQTTAsync_responseOptions* response);
 
 
 /** 
@@ -866,7 +866,7 @@ DLLExport int MQTTAsync_unsubscribeMany(MQTTAsync handle, size_t count, char* co
   * @return ::MQTTASYNC_SUCCESS if the message is accepted for publication. 
   * An error code is returned if there was a problem accepting the message.
   */
-DLLExport int MQTTAsync_send(MQTTAsync handle, const char* destinationName, size_t payloadlen, void* payload, int qos, int retained,
+DLLExport int MQTTAsync_send(MQTTAsync handle, const char* destinationName, int payloadlen, void* payload, int qos, int retained,
 																 MQTTAsync_responseOptions* response);
 
 
diff --git a/src/MQTTClient.c b/src/MQTTClient.c
index 8bc659cd..5fd14f03 100644
--- a/src/MQTTClient.c
+++ b/src/MQTTClient.c
@@ -970,15 +970,15 @@ int MQTTClient_connectURI(MQTTClient handle, MQTTClient_connectOptions* options,
 	if (m->c->sslopts)
 	{
 		if (m->c->sslopts->trustStore)
-			free(m->c->sslopts->trustStore);
+			free((void*)m->c->sslopts->trustStore);
 		if (m->c->sslopts->keyStore)
-			free(m->c->sslopts->keyStore);
+			free((void*)m->c->sslopts->keyStore);
 		if (m->c->sslopts->privateKey)
-			free(m->c->sslopts->privateKey);
+			free((void*)m->c->sslopts->privateKey);
 		if (m->c->sslopts->privateKeyPassword)
-			free(m->c->sslopts->privateKeyPassword);
+			free((void*)m->c->sslopts->privateKeyPassword);
 		if (m->c->sslopts->enabledCipherSuites)
-			free(m->c->sslopts->enabledCipherSuites);
+			free((void*)m->c->sslopts->enabledCipherSuites);
 		free(m->c->sslopts);
 		m->c->sslopts = NULL;
 	}
diff --git a/src/MQTTClient.h b/src/MQTTClient.h
index 4b2da833..222bea5c 100755
--- a/src/MQTTClient.h
+++ b/src/MQTTClient.h
@@ -462,19 +462,19 @@ typedef struct
 	int struct_version;	
 	
 	/** The file in PEM format containing the public digital certificates trusted by the client. */
-	char* trustStore;
+	const char* trustStore;
 
 	/** The file in PEM format containing the public certificate chain of the client. It may also include
 	* the client's private key. 
 	*/
-	char* keyStore;
+	const char* keyStore;
 	
 	/** If not included in the sslKeyStore, this setting points to the file in PEM format containing
 	* the client's private key.
 	*/
-	char* privateKey;
+	const char* privateKey;
 	/** The password to load the client's privateKey if encrypted. */
-	char* privateKeyPassword;
+	const char* privateKeyPassword;
  
 	/**
 	* The list of cipher suites that the client will present to the server during the SSL handshake. For a 
@@ -484,7 +484,7 @@ typedef struct
 	* those offering no encryption- will be considered.
 	* This setting can be used to set an SSL anonymous connection ("aNULL" string value, for instance).
 	*/
-	char* enabledCipherSuites;    
+	const char* enabledCipherSuites;
 
     /** True/False option to enable verification of the server certificate **/
     int enableServerCertAuth;
diff --git a/src/MQTTProtocolClient.c b/src/MQTTProtocolClient.c
index 3ba6280e..8fac01ef 100755
--- a/src/MQTTProtocolClient.c
+++ b/src/MQTTProtocolClient.c
@@ -666,15 +666,15 @@ void MQTTProtocol_freeClient(Clients* client)
 	if (client->sslopts)
 	{
 		if (client->sslopts->trustStore)
-			free(client->sslopts->trustStore);
+			free((void*)client->sslopts->trustStore);
 		if (client->sslopts->keyStore)
-			free(client->sslopts->keyStore);
+			free((void*)client->sslopts->keyStore);
 		if (client->sslopts->privateKey)
-			free(client->sslopts->privateKey);
+			free((void*)client->sslopts->privateKey);
 		if (client->sslopts->privateKeyPassword)
-			free(client->sslopts->privateKeyPassword);
+			free((void*)client->sslopts->privateKeyPassword);
 		if (client->sslopts->enabledCipherSuites)
-			free(client->sslopts->enabledCipherSuites);
+			free((void*)client->sslopts->enabledCipherSuites);
 		free(client->sslopts);
 	}
 #endif
diff --git a/src/SSLSocket.c b/src/SSLSocket.c
index 84769bb1..f3e2535b 100755
--- a/src/SSLSocket.c
+++ b/src/SSLSocket.c
@@ -449,7 +449,7 @@ void SSLSocket_terminate()
 int SSLSocket_createContext(networkHandles* net, MQTTClient_SSLOptions* opts)
 {
 	int rc = 1;
-	char* ciphers = NULL;
+	const char* ciphers = NULL;
 	
 	FUNC_ENTRY;
 	if (net->ctx == NULL)