[Exist-open] problem while starting exist

[karanjit c. <kar...@gm...>]

when i double click on the exist database startup
it gives me an error
org.exist.storage.btree.DBException: Database file dom.dbx has a storage
format incompatible with this version of eXist. Please do a backup/restore
of your data first. software version is 8;db version is 7.
please help

Regards
Karanjit Cheema