diff --git a/src-modules/org/opencms/workplace/tools/sites/CmsSiteDialogObject.java b/src-modules/org/opencms/workplace/tools/sites/CmsSiteDialogObject.java
index <HASH>..<HASH> 100644
--- a/src-modules/org/opencms/workplace/tools/sites/CmsSiteDialogObject.java
+++ b/src-modules/org/opencms/workplace/tools/sites/CmsSiteDialogObject.java
@@ -512,13 +512,14 @@ public class CmsSiteDialogObject {
         if ((site != null) && (site.getSiteMatcher() != null)) {

             uuid = (CmsUUID)site.getSiteRootUUID().clone();

         }

+        String errorPage = CmsStringUtil.isNotEmptyOrWhitespaceOnly(m_errorPage) ? m_errorPage : null;

         return new CmsSite(

             m_siteRoot,

             uuid,

             m_title,

             new CmsSiteMatcher(m_server),

             String.valueOf(m_position),

-            m_errorPage,

+            errorPage,

             matcher,

             m_exclusiveUrl,

             m_exclusiveError,
Do not write an empty error page attribute to the system configuration.