Thesis proposal near thesis defence I'm a PhD student in computer science. In my university, the PhD process is divided in the following steps:


Qualification exam
Research proposal exam: presentation of chosen topics and methodology and plan (near 1-1.5 year after PhD program begining)
Thesis proposal exam: presentation of done and remaining work (near 1-1.5 year after research proposal)
Thesis defence


I'm at the end of my PhD and basically at the end of the dissertation writing. I still have to write the last chapter about the validation results.

I still haven't done the «Thesis proposal exam» and will take it in mid august; then I expect to submit the dissertation draft at the end of august, for a defence expected in late september or in october.

I'm embarrassed, as I basically almost ended the dissertation, by the fact that the «Thesis proposal exam» presentation and the «Thesis defence» presentation will foregone be the same content. It look like the first one will be a sort of rehearsal of the second one.

How can I proceed to present a meaningful «Thesis proposal exam» and still having something new to say during my defence presentation?

Thanks.
As MadJack says in the comments, this is really something that you and your advisor need to sort out with the department.  Part of an advisor's responsibility to their students is to make sure that they don't end up in easily avoidable bureaucratic screw-ups like this.  So yes, you've failed, but your advisor has failed as well.

First thing to do, then, is to sit down with your advisor and figure out how serious a problem this is.  If it's something like JeffE suggests, and due to recent regulation changes, or if it's a requirement that is more pro-forma than serious, then there are likely good ways to deal with it.  For example, you might end up following the letter of the law and in fact having the proposal exam be essentially a dress rehearsal for the defense (and that might be considered to be OK).  Or the proposal exam might end up finding some problems that really do need to be addressed before you defend, and you will be grateful---you might be delayed, though, and that might or might not be a problem (you don't say where you are: in the US, delay is generally not a problem if your advisor can fund you; in some other countries it can be a major issue).

If the department is not flexible, however, and wants to make an issue of your failure to comply with the letter of the law, then the resolution will be very particular to the department, and that is something that you and your advisor will need to navigate together.