Outlook Keeps Asking for Password? 7 Fixes, in the Order That Works
Why does Outlook keep asking for my password?
When Outlook keeps asking for password details, it is usually because something has your old password and keeps trying it: a saved credential on the PC, a phone or second computer, or an Outlook profile that has gone stale. Less often it is a security prompt doing its job, or a sign that the password really did change. The fixes below are in the order that solves it most often for small offices on Microsoft 365; most take five minutes.
One check first. If the prompt is a Microsoft sign-in window (blue, with the Microsoft logo, maybe asking for a code from your phone), that is normal modern sign-in and usually means your session simply expired. If it is a small grey Windows box asking for a username and password over and over, keep reading.
1. Did the password actually change?
Before touching Outlook, open a browser and sign in at office.com with the same email address and the password you are typing. If that fails too, the problem is the password, not Outlook: it was reset, it expired, or the account is locked. Use “Forgot my password” if your office has that turned on, or ask whoever manages your Microsoft 365. If the browser sign-in works, the password is fine and one of the fixes below applies.
2. Clear the saved password on the PC
Windows keeps a copy of your Outlook password in Credential Manager. If it is old, Outlook tries it, fails, and asks again. Remove it:
- Close Outlook.
- Press the Windows key, type Credential Manager, open it, then choose Windows Credentials.
- Remove every entry that starts with MicrosoftOffice, Microsoft_OC or ADAL, and any that mention Outlook or your email address.
- Open Outlook and sign in once with the current password.
Microsoft’s page on Credential Manager shows where it lives in each version of Windows.
3. Find the other device that still has the old password
This is the one people miss. If you changed your password last week and your phone’s mail app, an old laptop at home, or a tablet in a drawer still has the old one, that device keeps failing to sign in, Microsoft locks the account for a few minutes, and the PC you are sitting at gets the prompt. Update the password on every device that has the account, or remove the account from devices you no longer use. If you cannot remember them all, your Microsoft 365 administrator can see the failed sign-ins and which device they come from.
4. Check the “always prompt” setting
In classic Outlook, an account can be set to ask every time. Open File → Account Settings → Account Settings, select the account, choose Change → More Settings → Security, and make sure Always prompt for logon credentials is not ticked. On old versions of Outlook the same tab has a Logon network security setting that must be Anonymous Authentication; Microsoft documents that case in Outlook continually prompts for password. Outlook 2016 and later no longer show that setting.
5. Make sure Outlook is new enough to sign in at all
Microsoft turned off the old username-and-password method for Microsoft 365 mail in 2022 and finished removing it for the remaining protocols afterwards (Microsoft’s basic authentication retirement). Outlook 2010 and 2013 cannot use the modern sign-in and will prompt forever. Outlook 2016 and later can, as long as Office is updated. If the PC is on an old perpetual Office, the fix is an update or a Microsoft 365 Apps subscription, not a password.
6. Build a fresh Outlook profile
If the browser sign-in works and the credentials are cleared but Outlook still loops, the profile itself may be damaged. Press the Windows key, type Control Panel, open Mail (Microsoft Outlook), choose Show Profiles → Add, give it a name, and add the account with the current password. Set the new profile as the default and open Outlook. Your mail lives on the server, so nothing is lost; the old profile can be removed once the new one works.
7. Rule out security software and VPNs
Antivirus products that inspect encrypted traffic, some VPNs and a few consumer routers can break the sign-in handshake and cause a loop that looks like a password problem. Test by pausing the antivirus’s web or email shield for a minute, or by disconnecting from the VPN, and opening Outlook again. If that stops the prompts, the product needs an exception for Microsoft 365, not Outlook.
Could the password prompt be a scam?
Yes, and this is worth a moment. Fake “your Outlook password has expired” emails and pop-ups are one of the most common ways attackers steal Microsoft 365 passwords. Real prompts come from Outlook or Windows themselves, never from an email asking you to “re-validate” by clicking a link. If a prompt appears inside a web page or an email, close it and sign in at office.com directly. If you think you already typed your password into a fake one, change it now and tell whoever manages your IT; stolen Microsoft 365 passwords are how invoice fraud usually starts. Our free password check shows whether a password has already leaked.
When is it time to call IT?
- Several people in the office get the prompt at once. That is a tenant-wide change (a policy, an expired setting, a licensing problem), not seven coincidences.
- The browser sign-in fails and you cannot reset the password yourself.
- It comes back every few days after the fixes above. Something is still trying the old password, and the sign-in logs will say what.
- You suspect the prompt was fake. The password change needs to happen on every service that shared it, and the mailbox should be checked for forwarding rules an attacker may have added.
For the businesses we manage across Polk County, this is a help desk call: we check the sign-in logs, clear the stuck credential, and tell you which device is causing it. See help desk support and Microsoft 365 management, or if your office has no one to call, our free IT assessment is a good first step. Call (321) 221-7117 or email info@itechplus.co.
