How can I open my .odt files with LibreOffice Writer

I’m on Ubuntu 15.10.

LibreOffice Version:
Build ID: 1:5.0.6-0ubuntu1
Locale: en-US (en_US.UTF-8

I have been using Libreoffice Writer for several years.
This week when I try to open any .odt file,
I get the following message:

Object not accessible.
The object cannot be accessed
due to insufficient user rights.

I am not able to open my files.
I am able to open libreoffice,
but it will not open my created files.

My Ubuntu Document Viewer won’t open .odt

This might help you: [SOLVED] LibreOffice, insufficient user rights when saving/opening / Applications & Desktop Environments / Arch Linux Forums