Microsoft To Do sign-in problem: get back into your tasks

A Microsoft To Do sign-in problem usually comes down to the wrong Microsoft account, a password or account access issue, or stale app/browser data on the device. The safest first fixes are to confirm the account you’re using, try the same account on the web, and clear cached sign-in data if the web version works. If To Do keeps looping back to sign-in or opens to a blank page, those checks usually tell you whether the problem is the app, the account, or Microsoft’s service.

Symptom

Microsoft To Do keeps asking me to sign in again

This usually shows up when you open the app or browser and get sent back to the sign-in screen, see a blank page, or find that your tasks do not load or sync. The exact message varies, and sometimes there is no message at all—just a loop between accounts or a page that never finishes loading.

Before you start

This applies to Microsoft To Do on the web, Windows, macOS, iPhone, and Android when you sign in with a Microsoft account or a work or school account.

• No administrator or sudo access is needed for the first checks.
• You do not need to restart the device right away.
• You do not need to back up anything before the first steps.
• First, make sure you know which Microsoft account should contain your tasks.
• If you use both personal and work or school accounts, note which one To Do should open with.

What the sign-in problem usually looks like

Microsoft To Do sign-in problems usually show up in one of a few ways.

• You get sent back to the sign-in screen after entering your email and password.
• The app opens to a blank page or never finishes loading your tasks.
• You’re signed in, but your lists are empty or not syncing.
• To Do keeps asking you to sign in again every time you open it.
• One device works, but another one cannot get past the login screen.

If the problem is only on one device or one browser, that usually points to the app, browser, or cached sign-in data. If it fails everywhere, the account itself is more likely to be the issue.

Is this your account, your app, or Microsoft itself?

The quickest way to separate those causes is to try the same account on the web.

Use a browser and sign in to the Microsoft account you expect to use with To Do. If your tasks and lists appear there, your account is probably fine and the issue is local to the app, browser, or device. If you cannot sign in on the web either, the problem is more likely the account itself, such as a bad password, a lock, a verification prompt, or a policy restriction on a work or school account.

If the web version works but the app does not, focus on cache, saved credentials, or app installation issues. If neither works and you see a Microsoft service message, there may be an outage or service degradation. In that case, trying the same sign-in from another device is still useful, but it may not fix anything until Microsoft clears the issue.

The quickest fixes to try first

Before you remove or reset anything, start with the safest checks.

These steps are safe and reversible. You do not need administrator rights for the first two, but clearing app data or reinstalling may require device access or admin approval depending on your setup.

1. Confirm you’re using the right Microsoft account. Sign out of any Microsoft account you may already have open in the browser, then sign in again with the address you normally use for To Do. If you have both personal and work or school accounts, it is easy to land on the wrong one and think the app is broken. If the wrong account opens, switch accounts and check whether your tasks appear. If they do, the sign-in problem was really an account mix-up.
2. Reset the password if you cannot get past sign-in anywhere. If the web sign-in fails too, reset the password for that Microsoft account and try again with the new password. If your account uses extra verification, complete that step before testing To Do again. If password reset does not help and the account still fails on the web, the issue is probably not just cached login data.
3. Check that your connection is working. Open another site or app that needs the internet. If that also fails, fix the connection first. To Do can get stuck on a blank sign-in page if the device cannot reach Microsoft’s login services reliably.
4. Clear browser cache or app data, then try again. If you use To Do in a browser, clear cached site data for Microsoft sign-in pages and reload the site. In the browser, open the site data settings page for the browser you use and remove data for Microsoft sign-in and To Do.

Browser settings > Privacy and security > Site data / Cookies and site data

If you use the desktop or mobile app, sign out if possible, then close the app completely and reopen it.

If the app still loops back to sign-in, reinstalling it is the next reversible step. Do that only after the account and browser checks above, because reinstalling does not help if the account itself is locked.

5. Try a fresh sign-in from another browser or device. If one browser keeps looping, use another browser. If one phone or computer fails, try a second one. A clean test often tells you whether the problem lives in the app or in the account.

If you get a blank page, the fastest clue is usually whether the same account works in a different browser session. If it does, your original browser likely has stale cookies, blocked pop-ups, or a sign-in extension interfering with Microsoft’s login flow.

How to check that sign-in is working again

Once you think the fix worked, verify it in a way that proves syncing is back.

1. Open Microsoft To Do on the same account you just used to sign in. Your lists should load without another sign-in prompt. If they do not, the sign-in may have worked only halfway.
2. Check that existing tasks appear. Open a list you know should contain tasks. If the list appears with the expected items, the account is connected properly.
3. Make a small change and watch for sync. Add a simple test task or mark one item complete, then wait briefly and check whether the same change appears in the browser version or on another device.
4. Confirm on a second device or in the web app. Open Microsoft To Do on another device, or sign in through the browser on the same account. If the new task and the status change show up there too, sync is working again.

If the app opens and your tasks are visible on one device but never appear anywhere else, the login problem may be fixed but sync is still blocked by the account, the network, or the service.

If it still won’t let you in

If the usual fixes fail, the problem is often outside the To Do app itself.

A work or school account can be blocked by your organization’s sign-in policy, password rules, or device compliance checks. If that account works on the web but not in the app, your organization may require a managed device, a fresh authentication session, or approval from an admin.

Two-factor authentication can also interrupt sign-in if the approval prompt never arrives, the authenticator app is out of sync, or the phone number on the account is no longer correct. In that case, complete the verification step first, then try To Do again.

If Microsoft services are having an outage, the app may refuse to sign in even when your password is correct. A web sign-in test from another device is the clearest way to tell whether the issue is widespread.

If your account is locked or flagged for suspicious activity, you usually need to clear that account issue first before To Do will stop looping. Once the account is restored, sign out everywhere you can, then sign back in on the device you want to use most.

Conclusion

If To Do still refuses to sign in after the web test, deal with the account status before you keep changing the app. Once you can sign in on the web and on a second device, go back to the original device and clear its cached sign-in data or reinstall the app if needed.

Frequently Asked Questions

Why does Microsoft To Do keep asking me to sign in again?

That usually means the app cannot keep a valid session. The most common causes are the wrong account, stale browser or app data, a blocked verification step, or a sign-in policy on a work or school account.

Can I use Microsoft To Do without signing in?

No. To Do needs a Microsoft account or work/school account to sync tasks across devices.

What if To Do works in the browser but not the app?

That points to the app, device, or cached sign-in data. Clear the app’s cached credentials or reinstall the app after you confirm the account works on the web.

How do I know if Microsoft is having an outage?

If the same account fails on multiple devices and the web sign-in also breaks, check whether Microsoft’s services are having a wider sign-in problem. If another account works normally, the issue is more likely tied to your account rather than an outage.