There needs to be more details about the use case.

Which formats of Excel and Word are involved?

Also, which kind of protection.  I assume this is protections on fields, sheets, and pages of various kinds.

Generally, those protections can't be preserved in importing into OpenOffice (there are serious incompatibilities in the way they are done between Microsoft formats and ODF), so they tend to be dropped.  It works in the other direction too. An ODF document with protections set will lose those protections when imported (as an ODF document) into Microsoft Office.  This is, in fact, one of the easier ways to remove those protections -- opening in the other product and saving them back.

To preserve the protection in OpenOffice might well require the user to provide the password so that the protection could be preserved if saved as ODF.  If saved back as the original Microsoft format, there are alternatives to preserving some protections.  I don't think they are cheap or easy.

I disagree that this is a defect, however undesirable.  There has never been a promise to preserve such functionality.  I am changing this to an enhancement request and raising the complexity.  

[PS: It is trivial to defeat protection even if supported.  Protection is more for preventing accidental modifications.  Malicious modification is child's play.  There should be a greater concern that using passwords for protection (not for encryption) exposes the password to discovery by someone with malicious intent.]

Hello
I can't reproduce your error could you give more specifics?
what steps did you do?
regards

without information to reproduce the bug.