Important: This article only applies to parents/caregivers activating a home account with their child’s school code. If you are a teacher or student seeing error 100405 while trying to launch My Math Academy or My Reading Academy in class, please see our Classroom Access Troubleshooting for Error 100405 article.
Applies to: One-time Home Account Activation using your child’s school code (not everyday sign-in).
Summary: During activation, you may see a Login and Password Sync pop-up if the email you entered already exists on another Age of Learning account (e.g., ABCmouse, Adventure Academy, or a prior school login). This is normal. Follow the steps below to complete activation—or fix Error 100405 if the sync doesn’t finish.
What you’ll see during activation (two screens)
1) Login and Password Sync pop-up
You’ll see two buttons here:
Continue Sync
Revise Username & Password
This pop-up is the initial sync check. If Continue Sync succeeds, you’ll move on with activation. If the system confirms a conflict, you’ll be taken to the separate Conflicting Account screen described next. If the sync fails before that, you may see Error 100405.
2) Conflicting Account resolution screen
If your email is already tied to another account, you’ll see two options:
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Remove Conflicting Account
Deletes the conflicting account for this product so you can proceed with your district-issued account/email.
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Update Conflicting Account
Keeps your existing account by assigning it a new email address. You’ll enter the new email and verify the existing account’s password. Your district-issued account then keeps the original email so you can finish activation.
Which option should I choose on the Conflicting Account screen?
Choose Remove Conflicting Account if you do not need the old account tied to this email for this product.
Choose Update Conflicting Account if you want to keep the old account active under a different email (recommended if you still use that account).
Not sure? Pick Update Conflicting Account so nothing is lost—you can always close or change that other account later.
If you see Error 100405 on the Sync pop-up
This means the background sync didn’t complete (often before the Conflicting Account screen could appear). Your code is still valid—try these steps in order:
Open the activation link in a Private/Incognito window and click Continue Sync again.
Try a different browser or device (e.g., Chrome → Safari/Edge; mobile → desktop).
Click Revise Username & Password and enter a different email that isn’t used on any Age of Learning account (fastest path to completion).
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Want to keep your original email? Contact Support and include:
The email you used
The error code (100405)
The date/time you attempted activation
We can resolve the conflict on the backend and complete the link for you.
Quick reference
Sync pop-up: Continue Sync / Revise Username & Password
Conflict screen: Remove Conflicting Account / Update Conflicting Account
Error 100405: The sync failed. Use Private/Incognito, try another browser, or use a different email—or contact Support to keep your original email.
Related articles
How to Redeem Your Child’s Code and Activate Your Home Account
General Password and Login Troubleshooting (for everyday sign-in issues after activation)