i am getting error message "the current database design invalid. do you want to exit without updating the database". i'm getting this error message recently but unable to recollect what update i had done.
does this have any impact on any of the package feature?
I'd believe it is an error from Configuration Manager, not User Admin.
Take a look here: http://docs.oracle.com/cd/E23943_01/doc.1111/e10978/e01_user_if.htm#BABHCABI
(on the right there is a button "Update Database Design")
In a nutshell, this usually appears if you modify your custom metadata field (create a new one or more, or somehow modify anything), but attempt to close the applet without updating the database design. Note that changes in the applet are not immediately committed in the database, so if you leave the applet, they will be disregarded. No other harm should be done.