There have been reports that as a Psion 7 battery runs out there can be hard resets and corruption of files (as well as soft resests in some cases). This is due to power running out. The battery warning is not as effective as it should be. When you get the alert saying 'Recharge Batteries Now' you should stop using the machine and recharge to avoid the problems of above.

The corruption of files generally only happens with files that are on a CF (or other non-RAM storage) disks. This is because this is one of the first devices to lose power (along with thing such as the PCMCIA slot, microphone etc.). The System is interupted as it is writing to the CF card (i.e. saving the file) and the file therefore becomes corrupt. Once corrupt there is little to do but start the file again.

The recommended action is to store files being worked on in the RAM (i.e. C drive) and those in storage on the D or E drive. More can be read about this topic in the Psion 7 Site and on other websites.

Irrelavent Note: Part of this problem is caused by the batteries running out quickly (the very nature of Lithium-Ion batteries causes this). In the original OS the battery indicator on the toolbar was useless, it has been improved in the more recent OS build.