This feature is now available in the go-oo version of OOo. This also means that, when you edit & save an existing Excel document that has already been encrypted, it will get saved encrypted. Previously when you did this, Calc would save it un-encrypted and you would lose your password protection, which was not good and was a deal breaker for a certain segment of users.

The upstream effort of this feature is underway in the scsheetprotection02 CWS. That CWS also contains another enhancement for sheet and document structure protection (sounds similar but totally unrelated to this document encryption feature), and as soon as I take care of upstreaming that enhancement, I can push the whole CWS for upstream integration. The bad news is that, because that requires a change in the ODF file format & UI change, it will probably take some time before it can be integrated upstream. But I’m making slow but steady progress there, so I’ll keep you guys updated.

Meanwhile, please test the go-oo version for this encryption feature to see if there is any document that Calc fails to encrypt properly (that means Excel can’t open it), and report any bugs to us. I’ve done my own testing, but it’s never as good as many other users testing it. So, thanks!

P.S. Actually this feature has been available for at least two months in the 3.0 branch, but I wanted to see this bug fixed before writing a blog about this so that I could take a pretty screenshot with all texts displayed.