I did a ticket and s t i l l you not fix this from Site update manager in Joomla get this notification bcs your update server.
"Some update sites are disabled. You may want to check the Update Sites Manager.
Update: Could not open update site #4600 "VDATA_UPDATE_SITE", URL:
www.wdmtech.com/prod_updates/vdata-custom-upgrade.xml
Update: Could not open update site #4603 "VDATA_UPDATE_SITE", URL:
www.wdmtech.com/prod_updates/vdata-upgrade.xml
Before updating ensure that the update is compatible with your Joomla! installation.
You are strongly advised to make a backup of your site's files and database before you start updating."
