The computer could not set up a secure session with a domain controller

What it means

The computer couldn’t reach a domain controller. Often logged briefly at startup before the network is ready.

Why it matters

If it persists, users can’t sign in with domain accounts and Group Policy won’t apply.

What to do

• Check DNS settings point only to domain controllers.
• Test with nltest /sc_verify:yourdomain.local.

Find it with PowerShell

Get-WinEvent -MaxEvents 20 -FilterHashtable @{
  LogName = 'System'; Id = 5719
} | Select-Object TimeCreated, ProviderName, Message

Add -ComputerName SERVER to query another machine. Other event sources can reuse the same ID number, so check the ProviderName column.