How to Extend Windows Server Trial License Period

Windows Server evaluation versions are valid for 180 days. After this period, the server will experience forced shutdowns every hour and limited functionality. Fortunately, Microsoft allows you to extend the trial period up to 6 times, giving you a total of approximately 3 years (1,080 days) to evaluate the server.

This guide applies to Windows Server 2016, 2019, 2022, and 2025 evaluation editions.

Important Notes

• The evaluation version is for testing purposes only and should not be used for commercial purposes
• You can rearm the license up to 6 times (180 days × 6 = ~3 years)
• Each rearm resets the trial period to 180 days
• The server must be restarted after each rearm for changes to take effect
• An internet connection is recommended but not always required

Prerequisites

• Administrator privileges on the Windows Server
• Command Prompt or PowerShell access

Step-by-Step Instructions

Step 1: Check Current License Status

Before extending the trial period, check how many days are remaining and how many rearms are left.

Option 1: Using Command Prompt or PowerShell (as Administrator)

slmgr /dlv

or

slmgr -dlv

This will display a detailed license information window showing:

• Time-based activation expiration: Days remaining in current trial period
• Remaining Windows rearm count: Number of times you can still extend the trial (0-6)

Option 2: Quick Check

slmgr /dli

This shows a simpler summary of license information.

Step 2: Extend the Trial Period (Rearm)

Once you've confirmed you have rearms remaining, run the following command:

slmgr /rearm

or

slmgr -rearm

You should see a message: "Command completed successfully. Please restart the system for the changes to take effect."

Step 3: Restart the Server

Restart your Windows Server for the changes to take effect:

shutdown /r /t 0

or restart through the Start menu.

Step 4: Verify the Extension

After the server restarts, verify that the trial period has been extended:

slmgr /dlv

You should now see:

• Time-based activation expiration: Reset to approximately 180 days
• Remaining Windows rearm count: Decreased by 1

Quick Reference Commands

Maximum Trial Duration

• Initial trial period: 180 days
• Maximum rearms: 6 times
• Total possible evaluation time: 180 days + (180 days × 6) = 1,260 days (approximately 3.5 years)

Troubleshooting

Error: "The maximum allowed number of re-arms has been exceeded"

This means you've already used all 6 rearms. You will need to either:

• Purchase a full Windows Server license
• Reinstall Windows Server to get a fresh 180-day trial (note: this will erase all data)

Error: "Access Denied"

Make sure you're running Command Prompt or PowerShell as Administrator:

1. Press Windows Key + X
2. Select Command Prompt (Admin) or Windows PowerShell (Admin)

Rearm Didn't Work

• Ensure you restarted the server after running the rearm command
• Check if you have any rearms remaining with slmgr /dlv
• Verify you have an active internet connection

Server Still Shows Expiration Warning

• Make sure you restarted the server
• Wait a few minutes after restart for the license to update
• Run slmgr /dlv to verify the new expiration date

When to Rearm

It's recommended to rearm your Windows Server license:

• Before the trial expires: Ideally a few days before expiration
• Not repeatedly: Only rearm when you actually need more time
• After expiration: You can still rearm even after the trial has expired, but it's better to do it beforehand

What Happens If Trial Expires?

If you don't extend the trial before it expires:

• Server will shut down automatically every hour
• Limited functionality and features
• Persistent "Windows is not activated" watermark
• Various system features may stop working

Alternative: Converting to Full License

If you decide to purchase a Windows Server license, you can convert your evaluation version to a full license without reinstalling:

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

Replace the X's with your actual product key and adjust the edition name as needed (ServerStandard, ServerDatacenter, etc.).

Legal and Ethical Considerations

• Use the evaluation version only for testing and evaluation purposes
• Do not use evaluation versions for production environments
• Follow Microsoft's Software License Agreement
• Purchase a proper license if you plan to use Windows Server commercially

Summary

To extend your Windows Server trial license:

1. Open Command Prompt or PowerShell as Administrator
2. Run slmgr /rearm
3. Restart the server
4. Verify with slmgr /dlv

You can repeat this process up to 6 times for a total evaluation period of approximately 3 years.