How to Extend Windows Server Evaluation Period for Up to 3 Years

Before extending your evaluation period, you need to check how much time remains and how many rearm cycles you have left. Open PowerShell or Command Prompt as Administrator by right-clicking and selecting 'Run as administrator'.

slmgr -dlv

This command displays detailed license information including the 'Time-based activation expiration' date and 'Remaining Windows rearm count'. You can also use the shorter version:

slmgr.vbs /dli

Look for these key details in the output:

• Time-based activation expiration: Shows when your current evaluation period ends
• Remaining Windows rearm count: Shows how many extensions you have left (maximum 6)
• License Status: Should show 'Initial grace period' for evaluation editions

Now execute the rearm command to reset your 180-day evaluation period. Make sure you're still in the elevated PowerShell or Command Prompt window.

slmgr -rearm

The system will display a dialog box with the message: 'Command completed successfully. Please restart the system for the changes to take effect.' Click OK to acknowledge.

The rearm process communicates with Microsoft's activation servers to validate and reset your evaluation period. This is why an internet connection is mandatory for the command to work properly.

What happens during rearm:

• The system contacts Microsoft's servers to validate the rearm request
• Your evaluation period counter resets to 180 days
• The remaining rearm count decreases by 1
• A restart flag is set requiring a system reboot

The rearm changes only take effect after a system restart. You can restart manually through the Start menu, or use the command line for immediate restart.

To restart immediately via command line:

shutdown /r /t 0

Or schedule a restart in 60 seconds to save any open work:

shutdown /r /t 60

If you prefer a graceful restart with a custom message:

shutdown /r /t 300 /c "Restarting to apply Windows Server evaluation extension"

The /t parameter specifies the delay in seconds, and /c adds a custom message that users will see.

During the restart, Windows applies the new evaluation period settings. The desktop watermark showing the evaluation countdown will update to reflect the new 180-day period after the system boots.

After the system restarts, verify that the evaluation period was successfully extended. Open PowerShell or Command Prompt as Administrator again and run the license check command.

slmgr -dlv

Compare the results with your previous screenshot or notes. You should see:

• Time-based activation expiration: Now shows a date 180 days from today
• Remaining Windows rearm count: Decreased by 1 (e.g., from 6 to 5)
• License Status: Still shows 'Initial grace period'

You can also check the desktop watermark in the bottom-right corner, which should display the updated evaluation period countdown.

For a quick status check without detailed information:

slmgr /xpr

This command shows a simple dialog with your expiration date.

Verification steps:

1. Confirm the expiration date is 180 days from today
2. Verify the rearm count decreased by exactly 1
3. Check that the desktop watermark shows the new countdown
4. Test that the system no longer shows expiration warnings

If the dates don't match or the rearm count didn't decrease, the extension may have failed and you should repeat the process.

With successful rearm, you now have access to approximately 3 years of total evaluation time (6 rearms × 180 days = 1,080 days). Plan your usage strategically to maximize this period.

Create a tracking system for your rearm cycles:

# Create a simple log file to track rearms
echo "Rearm Date: $(Get-Date), Remaining Count: [Check with slmgr -dlv]" >> C:\rearm_log.txt

Set up automated reminders using Windows Task Scheduler or PowerShell:

# Calculate next rearm date (170 days from now for 10-day buffer)
$nextRearm = (Get-Date).AddDays(170)
Write-Host "Next rearm recommended: $nextRearm"

Best practices for evaluation management:

• Document each rearm: Keep a log of when you used each rearm cycle
• Set early reminders: Schedule alerts 10 days before expiration
• Plan production migration: Use the 3-year period to plan your licensing strategy
• Test conversion process: Practice converting evaluation to licensed version

Monitor your remaining rearms regularly:

# Quick check script
slmgr -dlv | Select-String "rearm", "expiration"

Several issues can prevent successful rearm execution. Here's how to diagnose and resolve the most common problems.

Issue 1: Rearm command fails with network error

The rearm command requires internet connectivity to validate with Microsoft's servers. Test your connection:

# Test internet connectivity
Test-NetConnection -ComputerName microsoft.com -Port 80

# Check DNS resolution
nslookup microsoft.com

If connectivity fails, resolve network issues before attempting rearm again.

Issue 2: "Access denied" or permission errors

Ensure you're running PowerShell or Command Prompt as Administrator:

# Check if running as admin
([Security.Principal.WindowsPrincipal] [Security.Principal.WindowsIdentity]::GetCurrent()).IsInRole([Security.Principal.WindowsBuiltInRole] "Administrator")

If this returns False, restart your command prompt as Administrator.

Issue 3: Rearm count shows 0 remaining

You've exhausted all rearm cycles. Check conversion options:

# Check current edition
DISM /online /Get-CurrentEdition

# List available target editions
DISM /online /Get-TargetEditions

You can convert to a licensed version using DISM with a valid product key:

DISM /online /Set-Edition:ServerStandard /ProductKey:XXXXX-XXXXX-XXXXX-XXXXX-XXXXX /AcceptEula

Issue 4: System still shows expiration warnings after rearm

Force a license refresh:

# Refresh license status
slmgr /ato

# Clear license cache
slmgr /cpky