If you're having issues with implementing bits described in the specs, you
might find it best to ping the Apache POI dev list for help. Most of the
Apache people who've worked with the Microsoft binary file formats are
If you're finding gaps in the published Microsoft specifications, the best
option is to contact the Microsoft docs team. They're really nice people!
And they want to help! They can't always help, because some bits of the
file formats are complicatedly not covered by the open specifications, but
often they can.
For the case where properties are found "in the wild" but missing from the
documentation, it's probably worth just dropping the Microsoft docs team
Link to the page of the docs you're following, give them the list of IDs
you've found, and ask if it is expected that those IDs are missing. Based
on past experience, they'll take a few days to find someone on the
relevant team, and either come back with a "whoops, our bad, will be fixed
in the next 1-2 releases of the docs" or "sorry, deliberately excluded