Can’t sign up for Microsoft Developer Program — Error 40901 & phone number already linked

Question

Hello Microsoft Support,

I am trying to join the Microsoft Developer Program for learning and hands-on practice purposes. My goal is to create a Microsoft 365 E5 Developer Sandbox so I can access and practice Microsoft products end-to-end.

I want to use Microsoft 365 applications and services such as Microsoft Word, Excel, PowerPoint, Outlook, Access, OneDrive, SharePoint, Microsoft Forms, Planner, as well as Power Platform tools including Power Automate and Power BI, all under one developer (learning) account.

However, I am unable to complete the signup process due to the following error:

“Your phone number is already associated with an existing developer account.” Error Code: 40901 MS-CorrelationId: [Moderator note: personal info removed]

It appears that my phone number (ending with 5141) is linked to an old or inaccessible developer account. The following accounts may be associated with this issue:

[Moderator note: personal info removed]

• [Moderator note: personal info removed]
• [Moderator note: personal info removed]

[Moderator note: personal info removed]

I kindly request your help to unlink or release my phone number from any existing developer accounts, so that I can create one Microsoft Developer (learning) account that allows me to access Microsoft 365 E5 products and Power Platform tools for educational and practice purposes.

I have been trying to resolve this issue for over a week and would really appreciate your assistance.

Thank you very much for your time and support.

Kind regards,

[Moderator note: personal info removed]

Answer 1

Hi Swapnil Wankhade

Thank you for reaching out to Microsoft Q&A Forum and sharing your experience.

Please note that our forum is a public platform, and I will modify your question to hide your personal information in the description. Kindly ensure that you hide any personal or organizational information the next time you post an error or other details to protect personal data.

I understand how frustrating it is to be blocked during the Microsoft Developer Program signup, especially when you are trying to set up an E5 Developer Sandbox for learning and hands‑on practice. The 40901 error usually indicates that the phone number is still associated with a previous or inactive Microsoft Developer Program account.

Please note that, as a forum moderator, I do not have access to the internal systems required to modify Developer Program profiles or unlink phone numbers from existing accounts. 

You can try visiting Dashboard - Microsoft 365 Dev Center using the account that was originally linked to your phone number. If you still have access, choose Delete Profile to remove the old Developer account. This may help release the phone number so you can use it again for a new registration. Please note that it can take some time, usually up to 60 days, before the number becomes available for reuse. 

If you no longer have access to the old profile or the steps above do not work, I recommend contacting Microsoft Developer Support for further assistance through the following link: Services Hub. Please note that this portal (Services Hub) is a paid ticket and access is subject to certain conditions, which you can review here: Services Hub sign in FAQs | Microsoft Learn 

If you need to create a new developer account right away, you might consider using a different phone number, such as a work mobile or secondary line, to complete the registration process immediately. 

Please let me know how you get on, as your feedback is valuable to the community. 

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Answer 2

Hi,

Hey, thanks for getting in touch about the problem you're having signing up for the Microsoft Developer Program. I get that it's a big deal for you to get into the Microsoft 365 E5 Developer Sandbox so you can learn and get some practice. I appreciate you trying to fix this on your end.

So, the error you're seeing – Your phone number is already linked to a developer account, with code 40901 – usually pops up when your number is already tied to another developer profile. This stops you from making a new account with that number. To fix this, we need to check and unlink your number from any old or inactive developer accounts. Sadly, you can't do this yourself; Microsoft Support has to step in.

Can you let me know if you still have access to any of the accounts you talked about? If not, we can verify your identity and send a request to release your number. After that's done, you should be able to make a new developer account and get your Microsoft 365 E5 sandbox going.

 

I hope this helps.

 

Best Regards,

Noel