This is a problem I experienced when ym Psion 7 was brand new. Since then it has recurred only once. The solution is simple but care must be taken. Dont balme me if something goes wrong (see site disclaimer).

The problem is you get an infoprint stating 'Replace Backup Battery', this persists even when you know that the battery is brand new and in place (before carryong out the recommended action make sure the battery is not flat - check the Battery Information dialog in the system screen [Ctrl+Shift+P]). This is caused by a faulty connection in the battery compartment.

To correct this problem open the back up battery compartment on the underside of the machine and remove the battery (use the stylus to do this). You will see a gold coloured piece of metal (the connector) on top of a piece of green electric board (the underside of the motherboard). Bend the connector up ever so slightly so that a better connection can be made (the connector is flexible use only a small amount of pressure). Replace the backup battery and close the compartment. The problem should now be solved.