"closes LibreOffice on host"

Either another instance of LibreOffice is accessing your personal settings or your personal settings are locked.
Simultaneous access can lead to inconsistencies in your personal settings. Before continuing, you should make sure user ‘’ closes LibreOffice on host ‘’.

Do you really want to continue?

That blank space for the username under this part of the message:

...sure user " closes LibreOffice on host ".
showed up for me when I let my laptop battery run out and abruptly shut down my Windows computer. For that instance I was using (x64) *and was running via QuickStarter.*

I found solutions, here at Ask LibreOffice and at the OpenOffice forum.

Following that on Windows, while the software was not running I went to %appdata%/LibreOffice/4, and deleted the .lock file like this. But you lose your settings and recent files this way.

Hopefully someone could find out the answer without these consequences.