Unfortunately it doesn't seem to recognize all of the previous hotfixes:

    This Incremental Installer can only be used with a properly installed
    Domino installation.
    Not valid Domino version was detected:
              901FP4HF71

That was as patched by https://www-304.ibm.com/support/docview.wss?uid=swg21657963

It's generally been my experience that one needs to remove any hotfixes before installing a later Fixpack.

Have you tried removing HF71 first?

Is that IF1? I had 9.0.1 FP4 IF3 installed and and FP5 install worked fine. IBM really need to get this stuff fixed. It should just work and if it needs to uninstall any IF or Hotfix, it should do so. 

However on my Notes client with IF2 installed it failed. 

FP5 inicorporates all of the previouse Hot Fixes and Interim Fixes, But you must remove any Hot Fixes previously installed prior to installing FP5.