Windows 10: Microsoft 365 Email address doesn't exist when signing in to Windows 11

I have a Microsoft 365 Business Email account and it is working perfectly fine on Microsoft 365 Apps but when I am trying to sign in to windows, it says the email address doesn't exist. I don't know why.

:)

 

I can’t sign in Microsoft store with my university email why is this ?

I can’t sign in Microsoft store with my university email why is this ?

comes up like the account doesn´t exists but i´m signed in the online version.

from: Microsoft 365 and Office / PowerPoint / For home / Windows

 

Microsoft account does not exist error - but it does exist...

Another example of my confusion:

Step 1: Windows/Start button is pressed in the bottom left.

Step 2: Above "Power", "Settings", "Pictures" and "Documents" is my account/email address that I'm currently using to post this question with (which also is the Microsoft account I have my 365 subscription tied to). I click on my account with my personalized icon.

Step 3: Above "Sign out" and "Lock" is "Change account settings" which I click.

Step 4: I'm brought to "Your info" which has my personalized icon, correct email address, listed as the administrator too. I select "Manage my Microsoft account" and am taken to account.microsoft.com and logged in to the same correct email/account. I can see on this page my 365 family subscription is still active and fine.

Step 5: I go back to the "Your info" pop up settings window and below "Manage my Microsoft account" is another link to "Verify", of which I click.

Step 6: The small Microsoft Sign in window appears with prepopulated text saying that the same exact email address that I'm signed in on my computer using, (of which has active 365 subscription and has no issues seen on account.microosft.com when I log in) doesn't exist. The exact text is as follows and red: "That Microsoft account doesn't exist. Enter a different account or get a new one."

Step 7: When trying to re-enter the same email address, and clicking "Next" in the bottom right of the window, the red text persists that the account doesn't exist.

I can't comprehend how my correct email address which has Microsoft subscriptions simply can't be found or 'doesn't exist'.

Apologies for the long-winded questions, but I'm trying to be as thorough as possible so that anyone can review this and hopefully have a better understanding of the issues I'm having. I'm getting a bit desperate to have this sorted out and any solutions would be extremely valuable to me.

 

change email address for Microsoft account

Changing email address on Office 365 might affect the subscription that you have. We recommend contacting

Microsoft Answer Desk first for more information before following the steps below.

Here is how you can change the email address on your Microsoft account:

• Sign in to
  Manage how you sign in to Microsoft
  and fill in the information needed.
• Once you are on the page of Manage how you sign in to Microsoft,
  select Add email under the
  Account alias.
• Choose the option Create a new email address or
  Add an existing email address as a Microsoft account alias.
• Click Add alias.
• Click Make primary (To make the new email address as primary alias, you need to verify it for security purposes then follow the instruction on the email to
  finish the process).

Note: It will take up to 48 hours for the change to your email address to be applied across all Microsoft services.