Try these steps in order:
- Use the Microsoft account sign-in helper: https://aka.ms/sign-in-helper
- Enter the Gmail address or phone number used for sign-in.
- If the tool detects a problem, follow the recovery steps it gives.
- Check whether the sign-in name is being entered exactly correctly.
- Verify the Gmail address spelling carefully.
- If another alias or phone number was ever added to the account, try that instead.
- If the password is correct but the account is no longer recognized, use the account recovery flow.
- On the recovery page, enter the email address, phone number, or Skype name used to sign in.
- Choose where to receive the security code.
- Enter the code, then set a new password.
- If the message still says “We couldn't find an account with that username” or “The Microsoft account you've entered does not exist”, read the guidance for My username and password have stopped working and use the support option there.
- If an unfamiliar recovery address or security info appears, review recent account activity if sign-in becomes possible.
- Go to Security basics.
- Select Review activity.
- If activity is not recognized, choose This wasn't me or Secure your account.
- Then change the password.
- If the account has not been signed in to for more than two years, it may have been deleted and can no longer be reopened.
- If standard recovery keeps failing, contact Microsoft Support through the public support flow and explain:
- the Gmail address says the account does not exist during sign-in,
- the same address appears associated with Microsoft elsewhere,
- recovery does not recognize the address.
- I can't sign in to my Microsoft account | Microsoft Support
- Microsoft account sign-in helper | Microsoft Support
- My username and password have stopped working | Microsoft Support
- What happens if there's an unusual sign-in to your account | Microsoft Support
- Link your Google account and Microsoft account | Microsoft Support