Check that you have the latest LAMS 2 Unix installer
See the downloads page.
If you are updating LAMS
Make sure you have the previous version of LAMS installed. You can find out what version you can update to on the downloads page
You are strongly recommended to backup your LAMS installation before updating to prevent losing any of the data you may have saved while using your current LAMS installation. The updater will prompt you to ask whether you want an automatic backup, otherwise you can backup manually by following the steps.