You can stop wasting time here. Your files will never open in your CS5 version and the mini-updates won't fix it. Whoever provided them needs to export them from his CC version as IDML or you need to sign up for Creative Cloud.
That error usually indicates that you are trying to open InDesign files created in later version of InDesign.
But why are none of the updates updating?
The files I am trying to open were creating using my programs. Then my computer died and I had to reinstall the software from the CD again.
Once I did that it is giving me this error when I try to open anything I created before.