How to Extend Windows Server 2025 Trial License?

Go Beyond the 180-Day Limit — Up to 3 Years of Evaluation

Narbulut · System Administration Guide

What Is Windows Server 2025 Evaluation Edition?

Microsoft offers a free 180-day Evaluation edition of Windows Server 2025, giving you full access to all features for testing purposes. However, this period may not be enough for lab environments, long-running PoC (Proof of Concept) projects, or training setups. The good news is that Microsoft allows you to extend this period up to 6 times — giving you a total of 180 days x 6 = 1,080 days (approximately 3 years) of evaluation time.

In this guide, we’ll walk you through how to check your remaining trial period, extend it using the slmgr /rearm command, and cover the important details you need to know.

1. Check Your Current License Status

Before extending the trial, you need to find out how many days are remaining and how many rearm attempts you have left. Use the slmgr /dlv command to check this information.

Steps:

1. Open Command Prompt or PowerShell as Administrator. (Right-click the Start menu → select “Windows Terminal (Admin)” or “Command Prompt (Admin)”.)
2. Type the following command and press Enter:

slmgr /dlv

In the dialog window that appears, pay attention to these two fields:

• Time remaining — How much time is left before your license expires (in days and minutes)
• Remaining Windows rearm count — Number of extensions remaining (starts at 6)

2. Extend the Trial Period: slmgr /rearm

After checking your license status, simply use the slmgr /rearm command to extend the trial. This command resets the 180-day evaluation period back to the beginning.

Steps:

1. Open Command Prompt or PowerShell as Administrator.
2. Type the following command and press Enter:

slmgr /rearm

When the command runs successfully, you’ll see this message:

Command completed successfully.
Please restart the system for the changes to take effect.

3. As indicated in the message, you must restart the server for the changes to take effect:

:: Restart from command line
shutdown /r /t 0

4. After the server restarts, run slmgr /dlv again to verify that the timer has been reset.

3. Extension Rights Table

Each time you run slmgr /rearm, one extension right is consumed. You have 6 in total:

4. PowerShell Script for Automated Monitoring

If you want to regularly monitor your trial period, use the following PowerShell script to quickly view your remaining time and rearm count:

# Windows Server 2025 License Status Check Script

# Get license information
$licenseInfo = Get-CimInstance -ClassName SoftwareLicensingProduct |
    Where-Object { $_.PartialProductKey -and $_.Name -like "*Windows*" }

# Calculate remaining time
$remainingMinutes = $licenseInfo.GracePeriodRemaining
$remainingDays = [math]::Floor($remainingMinutes / 1440)

# Get rearm count
$rearmInfo = Get-CimInstance -ClassName SoftwareLicensingService
$rearmCount = $rearmInfo.RemainingWindowsReArmCount

Write-Host "=================================="
Write-Host " Windows Server License Status"
Write-Host "=================================="
Write-Host "Remaining   : $remainingDays days"
Write-Host "Rearm Rights: $rearmCount / 6"
Write-Host "=================================="

if ($remainingDays -lt 30) {
    Write-Host "WARNING: Less than 30 days! Consider running rearm." -ForegroundColor Red
}

5. Common Issues and Solutions

6. What Happens After the Evaluation Period Expires?

Once all rearm rights are exhausted and the final 180-day period ends, Windows Server 2025 enforces these restrictions:

• A “This copy of Windows is not genuine” watermark appears on the desktop
• The server shuts down automatically every hour — causing service interruptions
• Personalization settings (desktop background, etc.) cannot be changed
• Windows Update continues to deliver security patches, but the experience remains limited

This is why it’s important to have a licensing plan in place as you approach the end of your evaluation period.

7. Upgrading from Evaluation to Full License

If you decide to upgrade to a fully licensed edition after your evaluation, you can do so directly from the command line without reinstalling:

:: Upgrade from Evaluation to Standard Edition
DISM /Online /Set-Edition:ServerStandard /ProductKey:XXXXX-XXXXX-XXXXX-XXXXX-XXXXX /AcceptEula

:: Upgrade from Evaluation to Datacenter Edition
DISM /Online /Set-Edition:ServerDatacenter /ProductKey:XXXXX-XXXXX-XXXXX-XXXXX-XXXXX /AcceptEula

Quick Action Summary