Hi @Dissyce Mike ,
Welcome to our forum!
Are you using an Outlook.com account?
If so, please kindly understand that the Outlook tag here we mainly focus on general issues about Outlook desktop client. Based on my research, i didn't find a method to restrict the devices to log in to your account. If you are concerned about someone else who have your password logging into your account, we recommend that you could try the below steps to protect your account:
- Sign out of your Microsoft account everywhere
- Change your password and enable Two-step verification.
If it doesn't help, it's suggested that you could post your case in dedicated forum for Outlook.com for more professional advice. Thanks for your understanding and support!
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