When Group Policy Objects (GPOs) mysteriously fail with "Inaccessible, Empty, or Disabled" errors, it typically indicates one of these core issues:

    
SYSVOL access problems - Clients can't reach the Domain Controller's policy store
    
DFS-R replication failures - Between domain controllers
 
    
DNS resolution issues - For DC locator service
    
Client-side policy processing corruption



First, gather intelligence from both client and server perspectives:

# Client-side diagnostic commands:
gpresult /h gpreport.html
gpresult /r
nltest /dsgetdc:yourdomain.com
dcdiag /test:dns /v /s:yourdc.yourdomain.com

# Server-side checks:
repadmin /replsummary
dfsrdiag backlog /rgname:"Domain System Volume" /rfname:"SYSVOL Share" /smem:DC1 /rmem:DC2

In Windows 10 (especially 1809+), credential caching behavior changed. Try resetting the machine account password:
# PowerShell solution for affected clients:
Reset-ComputerMachinePassword -Server yourdc.yourdomain.com -Credential (Get-Credential)

Manually verify clients can access the policy definitions:
# Test SYSVOL access from PowerShell:
Test-Path "\\yourdomain.com\SYSVOL\yourdomain.com\Policies\{GUID}"

# If this fails, check DFS-R health:
Get-WinEvent -LogName "DFS Replication" -MaxEvents 20 | 
    Where-Object {$_.LevelDisplayName -eq "Error"} | 
    Format-List Message,TimeCreated

Enable verbose logging to catch processing failures:
# Registry tweak for detailed logging:
reg add "HKLM\SOFTWARE\Microsoft\Windows NT\CurrentVersion\Diagnostics" /v GPSvcDebugLevel /t REG_DWORD /d 0x30002 /f

# Then check Event Viewer for:
Get-WinEvent -LogName "Microsoft-Windows-GroupPolicy/Operational" -MaxEvents 50 | 
    Where-Object {$_.LevelDisplayName -eq "Error"} | 
    Format-List Message,TimeCreated

For stubborn cases, recreate the machine's AD account and local policy store:
# On DC:
Remove-ADComputer -Identity "ProblemPC" -Confirm:$false
Add-ADComputer -Name "ProblemPC" -SAMAccountName "ProblemPC$" -Path "OU=Computers,DC=yourdomain,DC=com"

# On client (run as admin):
klist purge
gpupdate /force

Implement these proactive checks in your monitoring system:
# PowerShell monitoring script:
$GPOHealth = Invoke-GPUpdate -RandomDelayInMinutes 0 -Force
$GPOResult = gpresult /r /scope computer
if ($GPOResult -match "Inaccessible|Empty|Disabled") {
    Send-MailMessage -To "admin@yourdomain.com" -From "monitor@yourdomain.com" -Subject "GPO Failure Alert" -Body $GPOResult
}


When Group Policy Objects (GPOs) fail to apply with the cryptic "Inaccessible, Empty, or Disabled" message on some Windows 10 clients while others work perfectly in the same Server 2012 R2 domain, we're facing a classic "it works on my machine" scenario that demands systematic troubleshooting.
Before diving deep, let's confirm the basic sanity checks:
# Check domain controller connectivity:
Test-Connection DC1 -Count 1
Test-Connection DC2 -Count 1

# Verify DNS resolution:
Resolve-DnsName yourdomain.com | Select-Object Name,IPAddress

The standard gpresult might not reveal everything. Here's a more comprehensive approach:
# Get detailed GPO application status:
Get-GPResultantSetOfPolicy -ReportType Html -Path "C:\temp\GPOReport.html"

# Check specific GPO processing details:
$gpo = Get-GPO -Name "Your_GPO_Name"
$gpo | Get-GPOReport -ReportType Xml | Out-File "C:\temp\GPODetails.xml"

Since the error suggests accessibility issues, let's verify SYSVOL access programmatically:
# Test SYSVOL accessibility:
Test-Path "\\yourdomain.com\SYSVOL\yourdomain.com\Policies\{GUID}"

# Alternative method using .NET:
[System.IO.Directory]::Exists("\\yourdomain.com\SYSVOL\yourdomain.com\Policies")

When the server-side checks out, we need to examine client-side processing. Create a diagnostic script to capture all relevant data:
$logFile = "C:\temp\GPOTroubleshoot_$(Get-Date -Format yyyyMMdd-HHmmss).log"

# Capture network connectivity info:
ipconfig /all | Out-File $logFile -Append
nslookup yourdomain.com | Out-File $logFile -Append

# Check Group Policy service status:
Get-Service gpsvc | Out-File $logFile -Append

# Export registry settings related to GPO processing:
reg export "HKLM\SOFTWARE\Microsoft\Windows\CurrentVersion\Group Policy" "$env:TEMP\GP_Registry.reg"

In this case, the issue appeared suddenly on specific machines. Let's check for network isolation features that might interfere:
# Check Network Location Awareness status:
Get-NetConnectionProfile | Select-Object Name,NetworkCategory

# Verify firewall rules for domain communication:
Get-NetFirewallRule -DisplayGroup "Core Networking" | Where-Object { $_.Enabled -eq $true }

When all else fails, this comprehensive reset procedure often resolves stubborn GPO issues:
# Stop dependent services:
Stop-Service gpsvc -Force
Stop-Service netlogon -Force

# Clear local policy cache:
Remove-Item "$env:windir\System32\GroupPolicy\*" -Recurse -Force
Remove-Item "$env:windir\System32\GroupPolicyUsers\*" -Recurse -Force

# Reset network components:
netsh int ip reset
netsh winsock reset

# Reset policy-related registry keys:
reg delete "HKLM\SOFTWARE\Microsoft\Windows\CurrentVersion\Group Policy" /f
reg delete "HKLM\SOFTWARE\Microsoft\Windows\CurrentVersion\Policies" /f

# Restart services and force update:
Start-Service netlogon
Start-Service gpsvc
gpupdate /force

In persistent cases, the machine might need to re-authenticate with the domain:
# Remove from domain (requires local admin):
Remove-Computer -UnjoinDomaincredential "DOMAIN\AdminUser" -PassThru -Verbose -Restart

# After restart, rejoin domain:
Add-Computer -DomainName "yourdomain.com" -Credential "DOMAIN\AdminUser" -Restart

After applying fixes, verify with these commands:
# Check last GPO application results:
gpresult /r

# Get detailed processing information:
gpresult /h gpreport.html

# Verify SYSVOL access post-fix:
dir \\yourdomain.com\SYSVOL\yourdomain.com\Policies

Remember that GPO replication issues between domain controllers can sometimes manifest as "Inaccessible" errors on clients. Always verify GPO consistency across all DCs using repadmin commands.