The kerberos subsystem encountered a PAC verification failure.  This indicates that the PAC from the client <Computer name> in realm <Dominio name> had a PAC which failed to verify or was modified.  Contact your system administrator.

This problem may occur when certain specific services are not run as shared. To solve the problem check share processes listed below by running the DOS command:
    * Sc query HTTPFilter
    * Sc query KDC
    * Sc query Netlogon
    * Sc query NTLMssp
    * Sc query PolicyAgent
    * Sc query ProtectedStorage
    * Sc query SamSs
    * Sc query Eventlog
    * Sc query PlugPlay

Run a command at a time and press enter. The processes must have the value in the information section TYPE: 20 WIN32_SHARE_PROCESS
Otherwise, type, again from the command promt the following string: sc config Service Name type = share