package lightdm 1.18.2-0ubuntu2 failed to install/upgrade: sub-processo script post-installation instalado retornou estado de saída de erro 1

[Vanius Girodo Brito]

I remove a LightDM. A system don't started.
I reinstall lighdm and the mensage show to me.

ProblemType: Package
DistroRelease: Ubuntu 16.04
Package: lightdm 1.18.2-0ubuntu2
ProcVersionSignature: Ubuntu 4.4.0-34.53-generic 4.4.15
Uname: Linux 4.4.0-34-generic x86_64
NonfreeKernelModules: nvidia_uvm nvidia
ApportVersion: 2.20.1-0ubuntu2.1
AptOrdering:
 lightdm: Configure
 grub-common: Configure
 grub: Configure
 grub-pc-bin: Configure
 NULL: ConfigurePending
Architecture: amd64
Date: Mon Aug 15 09:57:24 2016
ErrorMessage: sub-processo script post-installation instalado retornou estado de saída de erro 1
InstallationDate: Installed on 2016-07-16 (30 days ago)
InstallationMedia: Ubuntu 16.04 LTS "Xenial Xerus" - Release amd64 (20160420.1)
LightdmConfig:
 [Seat:*]
 autologin-user=vanius
RelatedPackageVersions:
 dpkg 1.18.4ubuntu1.1
 apt 1.2.12~ubuntu16.04.1
SourcePackage: lightdm
Title: package lightdm 1.18.2-0ubuntu2 failed to install/upgrade: sub-processo script post-installation instalado retornou estado de saída de erro 1
UpgradeStatus: No upgrade log present (probably fresh install)