package samba4 (not installed) failed to install/upgrade: subprocess installed post-installation script returned error exit status 126

[hshuangfei]

After install samba4 by using command apt-get install samba4, prompt install error sometimes.

ProblemType: Package
DistroRelease: Ubuntu 12.04
Package: samba4 (not installed)
ProcVersionSignature: Ubuntu 3.2.0-24.39-generic 3.2.16
Uname: Linux 3.2.0-24-generic i686
ApportVersion: 2.0.1-0ubuntu8
Architecture: i386
Date: Tue Jul 3 05:25:18 2012
DuplicateSignature:
 Setting up samba4 (4.0.0~alpha18.dfsg1-4ubuntu2) ...
 /var/lib/dpkg/info/samba4.postinst: 14: /var/lib/dpkg/info/samba4.postinst: /usr/share/samba/setoption.pl: Permission denied
 dpkg: error processing samba4 (--configure):
  subprocess installed post-installation script returned error exit status 126
ErrorMessage: subprocess installed post-installation script returned error exit status 126
InstallationMedia: Ubuntu 11.10 "Oneiric Ocelot" - Release i386 (20111012)
SourcePackage: samba4
Title: package samba4 (not installed) failed to install/upgrade: subprocess installed post-installation script returned error exit status 126
UpgradeStatus: Upgraded to precise on 2012-05-02 (61 days ago)