diff --git a/inc/caldav-LOCK.php b/inc/caldav-LOCK.php
index 85bc2087..cff8ecd9 100644
--- a/inc/caldav-LOCK.php
+++ b/inc/caldav-LOCK.php
@@ -98,7 +98,7 @@ if ( count($unsupported) > 0 ) {
   }
   $error = new XMLElement("error", new XMLElement( "LOCK",$badprops), array("xmlns" => "DAV:") );
 
-  $request->DoResponse( 403, $error->Render(0,'<?xml version="1.0" ?>'), 'text/xml; charset="utf-8"');
+  $request->DoResponse( 422, $error->Render(0,'<?xml version="1.0" ?>'), 'text/xml; charset="utf-8"');
 }
 
 
diff --git a/inc/caldav-PROPFIND.php b/inc/caldav-PROPFIND.php
index 5af07e16..fd83f84c 100644
--- a/inc/caldav-PROPFIND.php
+++ b/inc/caldav-PROPFIND.php
@@ -318,7 +318,7 @@ if ( count($unsupported) > 0 ) {
   }
   $error = new XMLElement("error", new XMLElement( "propfind",$badprops), array("xmlns" => "DAV:") );
 
-  $request->DoResponse( 403, $error->Render(0,'<?xml version="1.0" ?>'), 'text/xml; charset="utf-8"');
+  $request->DoResponse( 422, $error->Render(0,'<?xml version="1.0" ?>'), 'text/xml; charset="utf-8"');
 }
 elseif ( $request->AllowedTo('read') ) {
 
diff --git a/inc/caldav-REPORT.php b/inc/caldav-REPORT.php
index 661d06f8..c9033e9f 100644
--- a/inc/caldav-REPORT.php
+++ b/inc/caldav-REPORT.php
@@ -214,7 +214,7 @@ if ( isset($unsupported) && count($unsupported) > 0 ) {
   }
   $error = new XMLElement("error", new XMLElement( "propfind",$badprops), array("xmlns" => "DAV:") );
 
-  $request->DoResponse( 403, $error->Render(0,'<?xml version="1.0" ?>'), 'text/xml; charset="utf-8"');
+  $request->DoResponse( 422, $error->Render(0,'<?xml version="1.0" ?>'), 'text/xml; charset="utf-8"');
 }
 else {