Solving the “Service Tag Not Programmed” Error After a Device Replacement Laptop

Technology can be unpredictable. One day, you fix a hardware issue, and the next day, your computer greets you with a cryptic error message. Similar issues may arise if you change some components in your PC or Laptop.

Service Tag Fault in PC or Laptop

Let’s say e.g. you just replace laptop screen or any component in your laptop or PC recently. Everything may seem fine at first, but after a few days, and suddenly you may face the following error message straight away or after a few days.

“The service tag has not been programmed. The system will not function properly without a service tag.”

Weird, right?

Not only that, but the service tag (which is like a serial number for your machine) displayed on the screen may be completely different from the one printed on the sticker underneath your laptop. You may feel a little confused as if something is off.

What’s a Service Tag, and Why Does It Matter?

A service tag is a unique identifier assigned to your device, especially on branded systems like Dell, HP, Lenovo, etc. It’s used by the manufacturer to track warranty status, support requests, device specifications, and more.

If your computer doesn’t have the correct service tag—or worse, if it shows a blank or incorrect one—it can:

  • Confuse support services
  • Interfere with some firmware updates
  • Trigger boot-time warning messages
  • Sometimes, cause the system to behave abnormally

How to Fix It

Here are the step-by-step process to fix the issue and the problem:

  1. Entered the BIOS/UEFI Settings
    You can usually do this by pressing F2, F10, or DEL right after turning on the laptop (before the OS starts loading).
  2. Find the Service Tag Menu
    In the BIOS settings menu and find the tab labeled as Service Tag Information. See if the field is blank or Service tag is different from the one shown at the bottom of your laptop or on the PC.
  3. Entered the Correct Service Tag
    Type the correct tag that is printed on the label at the bottom of the laptop or on your PC case.
  4. Saved and Restarted
    After saving the settings and rebooting, the system should boot normally—no error, no drama.

Problem solved!

Why This Happens: A Bit of Background

This issue often arises when hardware components are replaced, especially:

  • Motherboard replacements
  • Display assembly replacements (on some laptops, the tag info is stored in embedded firmware within the display or related modules)
  • System board swaps in desktops or AIOs

When a new motherboard or key component is installed, it may not carry over the original system information—including the service tag. In some cases, the part may come from a different device entirely, with its own tag (or none at all).

This isn’t limited to laptops either. Desktops, All-in-Ones, and even some custom-built systems that use branded firmware tools can encounter similar issues when key parts are replaced.

General Advice If You Encounter This

  • Check the physical label: The correct service tag is usually printed on a sticker somewhere on the chassis.
  • Enter BIOS/UEFI: Look for a field to manually enter or update the service tag.
  • Use manufacturer tools: Some brands (like Dell) have tools that let you flash the correct service tag at a low level (e.g., asset.com or asset_a209.com for Dell systems).
  • Don’t ignore the message: It might seem harmless, but incorrect service tags can mess with support and system updates later.

⚠️ Important Note: On many systems, updating the service tag is a one-time operation. Once you write it, you may not be able to change it again without special tools or admin access. Make sure you enter the correct one!