I have seen many forum posts asking how do you schedule backups for SQL Express databases and the answers always have similar responses that go something like:

“There is no SQL agent in Express…the only way to backup databases on a schedule is to write a script and call it from a batch file.”

I saw this recent Microsoft  knowledge base article and thought I would post a link to it here, it talks you through in detail how to schedule backups in SQL express using the above method:

http://support.microsoft.com/default.aspx?scid=kb;en-us;2019698&sd=rss&spid=2855