To be fair, I did NOT figure this out for myself but I found it and tested it to work.
kwsetyprewset
(Whoever you are, MAD-PROPS! for this)
He/She writes:
"I have tried all advices I so far found in this forum and also several previous similar advices - they did not work for me - I have then nevertleless tried to 'combine' document creation/opening/modifying in Word and at one point it really broke the spell - I can not unfortunatelly remember exactly what I did, but it was something like this:
1) soft reset device
2) Start / Office Mobile / Word
3) Create a new document (click on New)
4) type some text (just plain text - no formatting - it was 'plain text document') just a few characters
5) File / Save As...
6) I have selected type 'Plain Text'
7) It asked me whether I want to save it at 'Word document instead' - I clicked No.
8) I have powered off the device and did soft reset
9) Start file explorer, find the file (it was in My Device / My Documents), click on it - it opens Word again.
10) Add some formatting (I have selected part of text and changed font to bold)
11) Close Word - it asked whether to save it in Word format - this time I said Yes
12) Power-off the device and press soft reset again
Then all was good again."
I think the problem occurs when MS PocketWord attempts to claim the Notes file type. I remember that I tried to save a large note and I saved it as a PWord doc instead. On the next Sync, broken.
My GUESS is that when MS marks itself the owner of the note file type (even though it really "OWNS" them both) it then attempts to modify all files on the device for future use in PocketOffice. In doing so, all files are locked by POffice and thereby unmodifiable.
The KEY in the solution above is to modify a PWord doc and save it as a .txt or open a .txt (Note) from PWord and save it as a .doc. Answer "Yes" to perform the conversion and power off. Turn it BACK on and immediately Soft Reset the device. Doing this in any other order will not work.