# How to register your GPS maps MicroSD [![gps-maps-plug-play-800x673.png](https://brmb.support/uploads/images/gallery/2023-09/scaled-1680-/gps-maps-plug-play-800x673.png)](https://brmb.support/uploads/images/gallery/2023-09/gps-maps-plug-play-800x673.png) [![2columns-titles-gps-register.png](https://brmb.support/uploads/images/gallery/2022-07/scaled-1680-/2columns-titles-gps-register.png)](https://brmb.support/uploads/images/gallery/2022-07/2columns-titles-gps-register.png) *Technical guide – Backroad Map Books*
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## 1. Why Register Your MicroSD?
FeatureDescription
**Computer‑based map downloads**Access to the latest *Computer Maps* for macOS & Windows.
**Secure license storage**Keeps your **`gmapsupp.unl`** and **`gmapsupp.gma`** files safe in your account.
**Discounted updates**Receive future map releases at a reduced price.
**Priority technical support**Faster response for any Garmin‑map‑related issue.
> **Free Updates** – After registration you can download map updates for **60 days** at no charge. > If you bought an older version from a retailer, you may upgrade to the latest map release within that 60‑day window. > **Important:** > • A card that has already been registered **cannot** be registered again. > • If your card is “used” or already updated, the registration will fail.
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## 2. Prerequisites
StepActionNotes
1**Insert the MicroSD card**• If your computer has an SD‑card slot, insert the card directly. • If not, plug the card into your Garmin GPS and connect the GPS to your computer via USB.
2**Log in to Backroad Map Books**URL: [https://backroadmapbooks.com/account/login](https://backroadmapbooks.com/account/login) Create an account if you do not already have one.
3**Locate the license files**The required files (`gmapsupp.unl` and `gmapsupp.gma`) are in the **Garmin** folder on your MicroSD.
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## 3. Registration Workflow > All steps are performed on the *My GPS Maps* registration page. ### 3.1 Navigate to the Registration Page
1. After login, click the **“MY GPS MAPS”** button (top‑right). 2. On the resulting page, select **“Register SD”**. ![Registration Button](https://brmb.support/uploads/images/gallery/2025-03/reg.png)
### 3.2 Upload the Unlock Code & GMA File
FieldFileHow to select
**Unlock Code (`gmapsupp.unl`)**`gmapsupp.unl`Use the **Choose File** button to pick this file from the *Garmin* folder.
**Gma File (`gmapsupp.gma`)**`gmapsupp.gma`Use the **Choose File** button for the second field.
> **Tip:** > Double‑check that the files you pick are **exactly** the `.unl` and `.gma` files from the Garmin folder. Any mismatch will trigger an error. #### 3.3 Submit
1. Once both files appear in the form, click **SUBMIT**. 2. A green confirmation box will appear, and your product will be listed under “My Products”. ![Success Message](https://brmb.support/uploads/images/gallery/2025-03/regsuccess.png)
> **Result:** The MicroSD card is now registered to your Backroad Map Books account.
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## 4. Post‑Registration
- **Access the “Computer Maps”** – Log in, go to **“My Products”** and download the latest PC‑compatible maps. - **Update within 60 days** – Download updates for free. - **Backup your files** – Although the unlock codes are stored in the cloud, keep local copies of the `.unl` and `.gma` files on your computer for future reference.
[![product.png](https://brmb.support/uploads/images/gallery/2025-03/scaled-1680-/product.png)](https://brmb.support/uploads/images/gallery/2025-03/product.png)
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## 4. Common Error Messages & Fixes
ErrorCauseRemedy
**“No ESN data found with unlockCode”**ESN (Electronic Serial Number) missing or corrupted.Contact Backroad Map Books support (email: gps<at>backroadmapbooks.com).
**“Invalid File Uploaded”**Wrong file type chosen (e.g., a `.zip` instead of `.gma` or `.unl`).Re‑select the exact `.gma` and `.unl` files from the Garmin folder.
**“This card has already been registered”**Card was previously registered on another account or already updated.Not recoverable – you must purchase a new card or contact support for advice.
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## 5. Quick Reference
ActionShortcut
Log in`Ctrl+L` (Chrome)
Open registration**MY GPS MAPS** → **Register SD**
File picker`gmapsupp.unl` → **Choose File**; `gmapsupp.gma` → **Choose File**
Submit**SUBMIT** button
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*Prepared by the Backroad Map Books Technical Support Team*