Hi Branden,

> [...] When he turned the tablet PC back on,
> all of the data he had entered that day was gone. [...]

It seems very unlikely to me that the problem you describe
would be the HDD hardware cache. While it can be a factor for
data loss in power-failure or power-fault situations, I cannot
imagine it would hold-up writing data for an entire day...
unless there is some sort of fault in the drive firmware.

To be honest I cannot really see Windows file system caching
doing that either. The Windows system restore feature could
be a factor if your database is held somewhere that Windows
thinks it needs to protect.

If it were a different sort of application, where changes are
made to a copy of the file, I could imagine the copy being
lost of restart and the app reverting to the original file.

I would probably look at other protection software on the
same PC. Backup software (second-copy, syncback etc) that
could (perhaps) be configured to automatically restore copies
after failure (or could otherwise disrupt FBs file access).
Even anti-virus programs... could it (wrongly) have detected a
virus and quarrantined or otherwise blocked access.


But while we are talking unlikely...

Have you checked for the possibility that the PC was using
a virtualization or sandbox environment?

It is difficult to imagine that they could be using something
like VMware Workstation or VirtualBox without realising it...
but either of these have the capability of dropping all changes
made during a session.

But perhaps they are using a sandbox... something like
http://www.sandboxie.com/
where (at least some) harddrive writes are isolated and
discarded at the end of the session.

How they would "accidently" start their system inside a sandbox
or virtual PC environment I cannot say... but what you describe
of losing an entire day's work sounds more like what I get
(intentionally) using one of these environments than anything
else I can think of.

--
Geoff Worboys
Telesis Computing