Soporte Active Directory (windows2003)

He ejecutado el Microsoft IT Environment Health Scanner y me da estos
errores y advertencias.

time source (advertencia)
The DC01 PDC is not configured to synchronize time with a reliable time
source

lesss than two days (advertencia)
The DC01 domain controller is configured to allow time conections thare
are greater than 172800 seconds
The DC02 domain controller is configured to allow time conections thare
are greater than 172800 seconds
The DC03 domain controller is configured to allow time conections thare
are greater than 172800 seconds

The local Central Active Directory site contains the remote 10.0.51.0/16
subnet (tiene un DC03)
The local Central Active Directory site contains the remote 10.0.52.0/16
subnet (no DC)
The local Central Active Directory site contains the remote 10.0.53.0/16
subnet (no DC)

La red que tengo esta conectada a traves de VPN, y en sitios y servicios
de AD tengo lo siguiente:
Central
Servers
DC01
DC02
Sucursal
Servers
DC03
Subnets
10.0.50.0/16 (Central)
10.0.51.0/16 (Sucursal)
10.0.52.0/16 (Central)
10.0.53.0/16 (Central)

He revisado la configuracion de todo y aprece correcta, por que me da esos
errores y advertencias