Then I had to do a soft reset because of a recurrent problem with other
software.

Only to find that my document had reverted to the bare heading mentioned
above.

There is no "Save" entry on the menu in Word Mobile, leading me to assume
that saving is continuous. I gather this is not true, so when is the docment
saved? Just when I "hide" (or minimise) Word Mobile? Or when I close it from
Running Programs list? If the latter doesn't work (and why not?), why not?
And why does not soft reset send a close to each program to ensure that data
is not lost?

And just as a clutched straw, is there any back-up that I could have found?
I suppose if the file was never written then the file synchronisation would
not have helped either!

(Grrrr...)

There is very little solid information in your post to help... for
example, what does "bare heading" mean?

examples (and search tips) for info that would help;

did you see text being entered into the file?

did you name the file?

did you look in the directory sorted by date to find the most recent
file and check file sizes?

please define what you feel a "soft reset" is

did you run a windows search for something unique in the file.

Some of the above may be obvious to you, but, in order to help, we need
as much info as possible.

To expand on your base question, closing and re-opening the file assures
a "save"  fwiw, it's what I do when working with anything important.
You can force a "close" using <ctrl-Q> or using a task manager such as
VBar which I strongly recommend.

In addition, your reference to "a recurrent problem" seems to indicate
that better managing open apps with <ctrl-Q> or a task manager may be
the resolution of more than one problem as I suspect that you have too
many apps open and perhaps low memory.

Another good habit is to execute a soft reset each time you take the
device off of the charger.

It could be that you switched into or immediately created the "other"
lockup before the save could be executed or that the lockup stopped the
file write process just as it started.

I hope that by "soft reset" I mean the same as you!

I don't think that I have a problem with too many running programs. I
haven't found a need for a task manager since I can close programs with the
built-in settings feature, and I have that on a short-cut button. But I do
find the Close/OK button rather strange, in that in Word Mobile (and other
built-in WM5 apps) it closes the document (with save, I'm pleased to read!)
but not the program. But there is a desktop precedent for that, I suppose.

"Bare heading" just meant a place-holder first paragraph in the document. I
had named the document, since I had re-opened it in order to complete it
with the bulk of the text. All nicely visible, spell-checked and so forth.
Which is what I have now lost. I'm pretty confident that I am not going to
find a back-up version anywhere, given that you make no reference to such a
built-in feature.

The "recurrent problem" I referred to arises with Navigon-5, which came
pre-installed on my Loox. The GPS device appears to be read using a separate
thread. I guess this because if I close the program and then switch off the
PDA without waiting a few seconds for the GPS-reception light to stop
blinking, the GPS device is held open and cannot be used by any other
program (including a re-start of Navigon) thereafter. Because switching off
is almost reflex I keep forgetting this precaution, and have to do a soft
reset to re-enable GPS usage. I have wondered if a Task Manager would enable
me to find the orphan thread and kill it. But I suspect that the device
would remain allocated, so a soft reset would still be needed.