package fglrx-experimental-13 (not installed) failed to install/upgrade: subprocess installed post-removal script returned error exit status 1

[Aaron Zhang]

just cannot install the ATI HD 7450 driver. Additional driver of ubuntu provides me two driver options, although the driver can be activated, it always said: the driver is currently activated but not in use. What's more, there is a water mark saying "AMD Unsupported hardware" on the bottom right of the screen . please help. Thanks.

ProblemType: Package
DistroRelease: Ubuntu 12.04
Package: fglrx-experimental-13 (not installed)
ProcVersionSignature: Ubuntu 3.8.0-31.46~precise1-generic 3.8.13.8
Uname: Linux 3.8.0-31-generic x86_64
NonfreeKernelModules: fglrx
ApportVersion: 2.0.1-0ubuntu17.5
AptOrdering:
 fglrx-experimental-13: Purge
 fglrx-updates: Purge
Architecture: amd64
Date: Tue Oct 15 14:06:04 2013
DpkgTerminalLog:
 Removing fglrx-experimental-13 ...
 Purging configuration files for fglrx-experimental-13 ...
 update-rc.d: /etc/init.d/atieventsd exists during rc.d purge (use -f to force)
 dpkg: error processing fglrx-experimental-13 (--purge):
  subprocess installed post-removal script returned error exit status 1
DuplicateSignature: package:fglrx-experimental-13:(not installed):subprocess installed post-removal script returned error exit status 1
ErrorMessage: subprocess installed post-removal script returned error exit status 1
MarkForUpload: True
SourcePackage: fglrx-installer-experimental-13
Title: package fglrx-experimental-13 (not installed) failed to install/upgrade: subprocess installed post-removal script returned error exit status 1
UpgradeStatus: No upgrade log present (probably fresh install)