This seems to affect the associations of other MS Office file formats as well, I had the same issue with a .xlsx file...
** Summary changed: - Libreoffice lost association with docx files + Libreoffice lost association with docx/xlsx files -- You received this bug notification because you are a member of Desktop Packages, which is subscribed to libreoffice in Ubuntu. https://bugs.launchpad.net/bugs/872678 Title: Libreoffice lost association with docx/xlsx files Status in “libreoffice” package in Ubuntu: Confirmed Bug description: Since the last updates, "docx" files are not associated with LibreOffice, and they are opened with Archive Manager instead. Easily fixable by restoring the association manually, but this happened to me in two different systems and I did nothing to break the association. ProblemType: Bug DistroRelease: Ubuntu 11.10 Package: libreoffice 1:3.4.3-3ubuntu2 ProcVersionSignature: Ubuntu 3.0.0-12.20-generic 3.0.4 Uname: Linux 3.0.0-12-generic x86_64 ApportVersion: 1.23-0ubuntu3 Architecture: amd64 Date: Wed Oct 12 07:48:29 2011 InstallationMedia: Ubuntu 10.04 LTS "Lucid Lynx" - Release amd64 (20100427.1) SourcePackage: libreoffice UpgradeStatus: Upgraded to oneiric on 2011-09-05 (36 days ago) To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/libreoffice/+bug/872678/+subscriptions -- Mailing list: https://launchpad.net/~desktop-packages Post to : desktop-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~desktop-packages More help : https://help.launchpad.net/ListHelp