diff --git a/vncviewer/CConn.cxx b/vncviewer/CConn.cxx
index ab5c9cc..f8b45af 100644
--- a/vncviewer/CConn.cxx
+++ b/vncviewer/CConn.cxx
@@ -411,7 +411,7 @@
   ret = fl_utf8froma(buffer, size, str, len);
   assert(ret < size);
 
-  vlog.debug("Got clipboard data (%d bytes)", strlen(buffer));
+  vlog.debug("Got clipboard data (%d bytes)", (int)strlen(buffer));
 
   // RFB doesn't have separate selection and clipboard concepts, so we
   // dump the data into both variants.
diff --git a/vncviewer/Viewport.cxx b/vncviewer/Viewport.cxx
index 6c77e58..3d6f4a8 100644
--- a/vncviewer/Viewport.cxx
+++ b/vncviewer/Viewport.cxx
@@ -351,7 +351,7 @@
                      Fl::event_length() + 1);
     assert(ret < (Fl::event_length() + 1));
 
-    vlog.debug("Sending clipboard data (%d bytes)", strlen(buffer));
+    vlog.debug("Sending clipboard data (%d bytes)", (int)strlen(buffer));
 
     try {
       cc->writer()->clientCutText(buffer, ret);
diff --git a/vncviewer/parameters.cxx b/vncviewer/parameters.cxx
index 29a5397..713ac07 100644
--- a/vncviewer/parameters.cxx
+++ b/vncviewer/parameters.cxx
@@ -303,7 +303,7 @@
 
   LONG res = RegSetValueExW(*hKey, name, 0, REG_SZ, (BYTE*)&value, (wcslen(value)+1)*2);
   if (res != ERROR_SUCCESS) {
-    vlog.error(_("Failed to write parameter %s of type %s to the registry: %d"),
+    vlog.error(_("Failed to write parameter %s of type %s to the registry: %ld"),
                _name, "REG_SZ", res);
     return;
   }
@@ -324,7 +324,7 @@
   
   LONG res = RegSetValueExW(*hKey, name, 0, REG_DWORD, (BYTE*)&value, sizeof(DWORD));
   if (res != ERROR_SUCCESS) {
-    vlog.error(_("Failed to write parameter %s of type %s to the registry: %d"),
+    vlog.error(_("Failed to write parameter %s of type %s to the registry: %ld"),
                _name, "REG_DWORD", res);
     return;
   }
@@ -348,7 +348,7 @@
     if (res == ERROR_FILE_NOT_FOUND) {
       // The value does not exist, defaults will be used.
     } else {
-      vlog.error(_("Failed to read parameter %s from the registry: %d"),
+      vlog.error(_("Failed to read parameter %s from the registry: %ld"),
                  _name, res);
     }
     return false;
@@ -387,7 +387,7 @@
     if (res == ERROR_FILE_NOT_FOUND) {
       // The value does not exist, defaults will be used.
     } else {
-      vlog.error(_("Failed to read parameter %s from the registry: %d"),
+      vlog.error(_("Failed to read parameter %s from the registry: %ld"),
                  _name, res);
     }
     return false;
@@ -407,7 +407,7 @@
                              REG_OPTION_NON_VOLATILE, KEY_ALL_ACCESS, NULL,
                              &hKey, NULL);
   if (res != ERROR_SUCCESS) {
-    vlog.error(_("Failed to create registry key: %d"), res);
+    vlog.error(_("Failed to create registry key: %ld"), res);
     return;
   }
 
@@ -428,7 +428,7 @@
 
   res = RegCloseKey(hKey);
   if (res != ERROR_SUCCESS) {
-    vlog.error(_("Failed to close registry key: %d"), res);
+    vlog.error(_("Failed to close registry key: %ld"), res);
   }
 }
 
@@ -444,7 +444,7 @@
     if (res == ERROR_FILE_NOT_FOUND) {
       // The key does not exist, defaults will be used.
     } else {
-      vlog.error(_("Failed to open registry key: %d"), res);
+      vlog.error(_("Failed to open registry key: %ld"), res);
     }
     return NULL;
   }
@@ -477,7 +477,7 @@
 
   res = RegCloseKey(hKey);
   if (res != ERROR_SUCCESS){
-    vlog.error(_("Failed to close registry key: %d"), res);
+    vlog.error(_("Failed to close registry key: %ld"), res);
   }
   
   return servername;