diff --git a/ares_gethostbyaddr.c b/ares_gethostbyaddr.c
index a0a90f6b..a8ca0f57 100644
--- a/ares_gethostbyaddr.c
+++ b/ares_gethostbyaddr.c
@@ -190,18 +190,18 @@ static int file_lookup(struct ares_addr *addr, struct hostent **host)
     char tmp[MAX_PATH];
     HKEY hkeyHosts;
 
-    if (RegOpenKeyEx(HKEY_LOCAL_MACHINE, WIN_NS_NT_KEY, 0, KEY_READ,
+    if (RegOpenKeyExA(HKEY_LOCAL_MACHINE, WIN_NS_NT_KEY, 0, KEY_READ,
                      &hkeyHosts) == ERROR_SUCCESS)
     {
       DWORD dwLength = MAX_PATH;
-      RegQueryValueEx(hkeyHosts, DATABASEPATH, NULL, NULL, (LPBYTE)tmp,
+      RegQueryValueExA(hkeyHosts, DATABASEPATH, NULL, NULL, (LPBYTE)tmp,
                       &dwLength);
-      ExpandEnvironmentStrings(tmp, PATH_HOSTS, MAX_PATH);
+      ExpandEnvironmentStringsA(tmp, PATH_HOSTS, MAX_PATH);
       RegCloseKey(hkeyHosts);
     }
   }
   else if (platform == WIN_9X)
-    GetWindowsDirectory(PATH_HOSTS, MAX_PATH);
+    GetWindowsDirectoryA(PATH_HOSTS, MAX_PATH);
   else
     return ARES_ENOTFOUND;
 
diff --git a/ares_gethostbyname.c b/ares_gethostbyname.c
index caab6ae4..7c46d96c 100644
--- a/ares_gethostbyname.c
+++ b/ares_gethostbyname.c
@@ -351,18 +351,18 @@ static int file_lookup(const char *name, int family, struct hostent **host)
     char tmp[MAX_PATH];
     HKEY hkeyHosts;
 
-    if (RegOpenKeyEx(HKEY_LOCAL_MACHINE, WIN_NS_NT_KEY, 0, KEY_READ,
+    if (RegOpenKeyExA(HKEY_LOCAL_MACHINE, WIN_NS_NT_KEY, 0, KEY_READ,
                      &hkeyHosts) == ERROR_SUCCESS)
     {
       DWORD dwLength = MAX_PATH;
-      RegQueryValueEx(hkeyHosts, DATABASEPATH, NULL, NULL, (LPBYTE)tmp,
+      RegQueryValueExA(hkeyHosts, DATABASEPATH, NULL, NULL, (LPBYTE)tmp,
                       &dwLength);
-      ExpandEnvironmentStrings(tmp, PATH_HOSTS, MAX_PATH);
+      ExpandEnvironmentStringsA(tmp, PATH_HOSTS, MAX_PATH);
       RegCloseKey(hkeyHosts);
     }
   }
   else if (platform == WIN_9X)
-    GetWindowsDirectory(PATH_HOSTS, MAX_PATH);
+    GetWindowsDirectoryA(PATH_HOSTS, MAX_PATH);
   else
     return ARES_ENOTFOUND;
 
diff --git a/ares_init.c b/ares_init.c
index 31a0e443..fac5482c 100644
--- a/ares_init.c
+++ b/ares_init.c
@@ -585,7 +585,7 @@ static int get_REG_SZ(HKEY hKey, const char *leafKeyName, char **outptr)
   *outptr = NULL;
 
   /* Find out size of string stored in registry */
-  res = RegQueryValueEx(hKey, leafKeyName, 0, NULL, NULL, &size);
+  res = RegQueryValueExA(hKey, leafKeyName, 0, NULL, NULL, &size);
   if ((res != ERROR_SUCCESS && res != ERROR_MORE_DATA) || !size)
     return 0;
 
@@ -596,7 +596,7 @@ static int get_REG_SZ(HKEY hKey, const char *leafKeyName, char **outptr)
     return 0;
 
   /* Get the value for real */
-  res = RegQueryValueEx(hKey, leafKeyName, 0, NULL,
+  res = RegQueryValueExA(hKey, leafKeyName, 0, NULL,
                         (unsigned char *)*outptr, &size);
   if ((res != ERROR_SUCCESS) || (size == 1))
   {
@@ -627,7 +627,7 @@ static int get_REG_SZ_9X(HKEY hKey, const char *leafKeyName, char **outptr)
   *outptr = NULL;
 
   /* Find out size of string stored in registry */
-  res = RegQueryValueEx(hKey, leafKeyName, 0, &dataType, NULL, &size);
+  res = RegQueryValueExA(hKey, leafKeyName, 0, &dataType, NULL, &size);
   if ((res != ERROR_SUCCESS && res != ERROR_MORE_DATA) || !size)
     return 0;
 
@@ -638,7 +638,7 @@ static int get_REG_SZ_9X(HKEY hKey, const char *leafKeyName, char **outptr)
     return 0;
 
   /* Get the value for real */
-  res = RegQueryValueEx(hKey, leafKeyName, 0, &dataType,
+  res = RegQueryValueExA(hKey, leafKeyName, 0, &dataType,
                         (unsigned char *)*outptr, &size);
   if ((res != ERROR_SUCCESS) || (size == 1))
   {
@@ -683,11 +683,11 @@ static int get_enum_REG_SZ(HKEY hKeyParent, const char *leafKeyName,
   for(;;)
   {
     enumKeyNameBuffSize = sizeof(enumKeyName);
-    res = RegEnumKeyEx(hKeyParent, enumKeyIdx++, enumKeyName,
+    res = RegEnumKeyExA(hKeyParent, enumKeyIdx++, enumKeyName,
                        &enumKeyNameBuffSize, 0, NULL, NULL, NULL);
     if (res != ERROR_SUCCESS)
       break;
-    res = RegOpenKeyEx(hKeyParent, enumKeyName, 0, KEY_QUERY_VALUE,
+    res = RegOpenKeyExA(hKeyParent, enumKeyName, 0, KEY_QUERY_VALUE,
                        &hKeyEnum);
     if (res != ERROR_SUCCESS)
       continue;
@@ -718,7 +718,7 @@ static int get_DNS_Registry_9X(char **outptr)
 
   *outptr = NULL;
 
-  res = RegOpenKeyEx(HKEY_LOCAL_MACHINE, WIN_NS_9X, 0, KEY_READ,
+  res = RegOpenKeyExA(HKEY_LOCAL_MACHINE, WIN_NS_9X, 0, KEY_READ,
                      &hKey_VxD_MStcp);
   if (res != ERROR_SUCCESS)
     return 0;
@@ -750,7 +750,7 @@ static int get_DNS_Registry_NT(char **outptr)
 
   *outptr = NULL;
 
-  res = RegOpenKeyEx(HKEY_LOCAL_MACHINE, WIN_NS_NT_KEY, 0, KEY_READ,
+  res = RegOpenKeyExA(HKEY_LOCAL_MACHINE, WIN_NS_NT_KEY, 0, KEY_READ,
                      &hKey_Tcpip_Parameters);
   if (res != ERROR_SUCCESS)
     return 0;
@@ -772,7 +772,7 @@ static int get_DNS_Registry_NT(char **outptr)
     goto done;
 
   /* Try adapter specific parameters */
-  res = RegOpenKeyEx(hKey_Tcpip_Parameters, "Interfaces", 0,
+  res = RegOpenKeyExA(hKey_Tcpip_Parameters, "Interfaces", 0,
                      KEY_QUERY_VALUE | KEY_ENUMERATE_SUB_KEYS,
                      &hKey_Interfaces);
   if (res != ERROR_SUCCESS)
@@ -1463,7 +1463,7 @@ static int get_SuffixList_Windows(char **outptr)
     return 0;
 
   /* 1. Global DNS Suffix Search List */
-  if (RegOpenKeyEx(HKEY_LOCAL_MACHINE, WIN_NS_NT_KEY, 0,
+  if (RegOpenKeyExA(HKEY_LOCAL_MACHINE, WIN_NS_NT_KEY, 0,
       KEY_READ, &hKey) == ERROR_SUCCESS)
   {
     if (get_REG_SZ(hKey, SEARCHLIST_KEY, outptr))
@@ -1475,7 +1475,7 @@ static int get_SuffixList_Windows(char **outptr)
 
   /* 2. Connection Specific Search List composed of:
    *  a. Primary DNS Suffix */
-  if (RegOpenKeyEx(HKEY_LOCAL_MACHINE, WIN_DNSCLIENT, 0,
+  if (RegOpenKeyExA(HKEY_LOCAL_MACHINE, WIN_DNSCLIENT, 0,
       KEY_READ, &hKey) == ERROR_SUCCESS)
   {
     get_REG_SZ(hKey, PRIMARYDNSSUFFIX_KEY, outptr);
@@ -1485,17 +1485,17 @@ static int get_SuffixList_Windows(char **outptr)
     return 0;
 
   /*  b. Interface SearchList, Domain, DhcpDomain */
-  if (!RegOpenKeyEx(HKEY_LOCAL_MACHINE, WIN_NS_NT_KEY "\\" INTERFACES_KEY, 0,
+  if (!RegOpenKeyExA(HKEY_LOCAL_MACHINE, WIN_NS_NT_KEY "\\" INTERFACES_KEY, 0,
       KEY_READ, &hKey) == ERROR_SUCCESS)
     return 0;
   for(;;)
   {
     keyNameBuffSize = sizeof(keyName);
-    if (RegEnumKeyEx(hKey, keyIdx++, keyName, &keyNameBuffSize,
+    if (RegEnumKeyExA(hKey, keyIdx++, keyName, &keyNameBuffSize,
         0, NULL, NULL, NULL)
         != ERROR_SUCCESS)
       break;
-    if (RegOpenKeyEx(hKey, keyName, 0, KEY_QUERY_VALUE, &hKeyEnum)
+    if (RegOpenKeyExA(hKey, keyName, 0, KEY_QUERY_VALUE, &hKeyEnum)
         != ERROR_SUCCESS)
       continue;
     if (get_REG_SZ(hKeyEnum, SEARCHLIST_KEY, &p) ||