hi, i had a runtime error when i wanted to upgrade L.O. 3.5 to 3.6, i did 2-3x a fresh install, then i did remove the L.O. folder wich was left in prog files x86 (it was "share" i think, so i did search on a forum, and i did del also the appdata folder from L.O., then it did work.
This sounds very much like it was due to the same underlying problem as bug 53006. See "Various problems with bundled extensions" at <https://wiki.documentfoundation.org/index.php?title=ReleaseNotes/3.6#Most_annoying_bugs> for the workaround (which is to remove a specific part of the LibreOffice appdata folder).
*** This bug has been marked as a duplicate of bug 53006 ***