The important step is to delete the User profile, as set out in tutorial cited above. A reinstall does not refresh this, and a purge may only remove program files, not the user configuration files. It can also happen that a user is trying to open only the one file, which has become unstable. If a new istall can create, save and open a small trial file, but cannot open the old file, then the problem may attach to that file; it may be possible to help if so.
Apache OpenOffice 4.1.3 on Xubuntu 16.04 (mostly 64 bit version) and infrequently on Win2K/XP
14 October 2016 was Pooh's 90th birthday