i recently installed samba on my laptop so that i could setup a file share for some stuff (music,ardour projects and documents) but since then no installation has properly succeeded. i could use the software but the installers (synaptic, software centre and software updater) all gave errors in 12.10 studio. I just tried to upgrade to 13.04 and got the error in the summary. I eventually managed to uninstall samba and try again and it worked fine but the fact that it happened and said my system might be unusable (this has happened to me in the past for other reasons so i was worried) made me quite concerned.
ProblemType: Package
DistroRelease: Ubuntu 13.04
Package: samba4 (not installed)
ProcVersionSignature: Ubuntu 3.8.0-19.13-lowlatency 3.8.8
Uname: Linux 3.8.0-19-lowlatency i686
ApportVersion: 2.9.2-0ubuntu8
AptOrdering: samba4: Configure
Architecture: i386
Date: Sun Apr 28 21:44:15 2013
ErrorMessage: subprocess installed post-installation script returned error exit status 255
InstallationDate: Installed on 2012-12-08 (140 days ago)
InstallationMedia: Ubuntu-Studio 12.04.1 "Precise Pangolin" - Release i386 (20120818)
MarkForUpload: True
SourcePackage: samba4
Title: package samba4 (not installed) failed to install/upgrade: subprocess installed post-installation script returned error exit status 255
UpgradeStatus: Upgraded to raring on 2013-04-28 (0 days ago)
Status changed to 'Confirmed' because the bug affects multiple users.