I have created a custom theme in portal 7.3 by saving the standard SAP_Tradeshow theme as ABC_theme. I assigned the customer_theme to the portal desktop.
My problem is sometimes the theme works properly but sometimes it the desktop loads default SAP_Tradeshow theme. At the same time, I checked in portal by navigating Content Administration --> Portal Display---> Theme Editor, I cannot see ABC_theme Under Customer Themes.
I also checked the portal server file system by navigating Drive:\usr\sap\SID\JXX\j2ee\cluster\apps\sap.com\com.sap.portal.design.urdesigndata\servlet_jsp\com.sap.portal.design.urdesigndata\root\themes\portal and Drive:\usr\sap\SID\JXX\j2ee\cluster\apps\sap.com\com.sap.portal.design.portaldesigndata\servlet_jsp\com.sap.portal.design.portaldesigndata\root\themes\portal (or) its, ABC_theme is available there.
It is not reflecting in portal application under Content Administration --> Portal Display---> Theme Editor now and then.
I attached the error page also. Why this is happening? How could i resolve this?