Microsoft To Do not connecting: fix sync and sign-in
If Microsoft To Do is not connecting, the usual causes are a stalled app, a bad sign-in session, or a Microsoft service problem. Start by checking your internet and account status, then force a sync or sign out and back in. If it still fails, the next fix depends on whether you’re on Windows, iPhone, Android, or the web.
Symptom
The exact message variesThis problem shows up when Microsoft To Do won’t load your lists, keeps spinning while syncing, asks you to sign in again and again, or shows a connection error while you try to open tasks. It can also look like one device is blank while another device still has everything.
Before you start
This applies to Microsoft To Do on Windows, iPhone, Android, and the web. No Administrator or sudo access is usually needed for the first checks, and you do not need to back up anything before you start.
Safe checks first:
- Open another website or app to see whether your internet connection is working.
- Check that you’re signed into the Microsoft account that actually holds your lists.
If you’re using a work or school account, a policy or permission change can also affect syncing.
What 'not connecting' usually looks like
The problem can show up in a few different ways. You might see a spinning sync indicator that never finishes, lists that stay blank, tasks that never appear on another device, or a message saying the app can’t connect. Some people get stuck in a sign-in loop, where Microsoft To Do asks them to sign in again and again but never finishes. Others can open the app, but only part of their data loads.
A connection problem is not always the same as a missing-task problem. If the app opens but one list is empty, that can be a sync delay, a bad account link, or a device-specific issue. If nothing loads anywhere, the app or service itself is more likely to blame. If one device works and another doesn’t, focus on the broken device first.
Check whether the problem is on your side or Microsoft’s side
Start with the simplest checks before changing settings. If your internet is down or flaky, Microsoft To Do may fail to sync even though the app itself is fine. Open a normal website or another Microsoft app to see if the connection is stable. If other apps also struggle, fix the network first.
Next, check whether you’re signed into the right Microsoft account. Microsoft To Do uses the account tied to your tasks, so a work account on one device and a personal account on another can make it look like syncing is broken when you’re actually looking at different task stores.
On the web, if the site loads but your lists do not, sign out and back in. If sign-in fails across multiple Microsoft services, the issue may be with your Microsoft account rather than To Do.
If the app works on one device but not another, that usually points to the device, not the service.
Also check for a service outage. If Microsoft’s cloud services are having trouble, you may not be able to fix it locally. In that case, wait and try again later instead of resetting anything.
The fixes that solve most Microsoft To Do connection problems
Work through these in order. They are the safest fixes and usually solve the problem before you get into anything more disruptive.
- Close Microsoft To Do completely and open it again.
If the app is stuck, force-closing it clears a temporary glitch. On Windows, quit the app from the taskbar or Task Manager. On iPhone or Android, swipe the app away from the app switcher, then reopen it. On the web, refresh the page or sign out and back in.
Microsoft To Do opens normally and starts loading your lists again.If that does not help, the app probably has a deeper sync problem rather than a temporary freeze.
- Check that you’re using the right account and sign out and back in.
If you rely on changes that have not synced yet, check which tasks were edited recently before you sign out. A local change that has not synced yet can be harder to sort out afterward.
Use the account menu inside Microsoft To Do and confirm the email address. If it’s wrong, switch to the account that actually holds your lists. Then sign out, close the app, reopen it, and sign in again.
Microsoft To Do > account menu > sign outThe app signs in cleanly with the same account you use on your other devices.If you still land in a sign-in loop, the saved session is probably corrupted or the account needs attention.
- Force a sync.
In the app, pull down to refresh where that gesture is available, or use the sync control if you see one. On the web, reload the page after signing in. A successful sync usually makes recent changes appear across devices.
Recent tasks and edits appear on all devices after a short wait.If nothing changes, the app may not be reaching Microsoft’s service yet.
- Update the app.
An outdated version can keep old sign-in or connection bugs. Update Microsoft To Do from the Microsoft Store on Windows, the App Store on iPhone, or Google Play on Android. On the web, make sure you are using a supported browser and refresh it fully.
Microsoft Store / App Store / Google Play > Microsoft To Do > UpdateYou’re on the current app version and the connection problem stops.If the issue returns right after updating, the cause is probably not just an old app build.
- Check date and time.
If the device clock is wrong, sign-in tokens can fail. Turn on automatic date and time on your phone or PC, then try again. This matters more than people expect, especially after a device has been off for a while or changed time zones.
Device settings > Date & time > Set automaticallyThe device shows the correct time and Microsoft To Do connects again.If the app still cannot connect, the clock was not the only problem.
- Clear the app cache where that option exists.
On Android, clear the app cache from the app settings if the app keeps failing to connect. On Windows, there is not a simple in-app cache button for every case, so the next step is usually to repair the app or use the web version to compare behavior. On iPhone, the usual approach is to remove and reinstall the app only after you have tried the simpler steps above.
Android settings > Apps > Microsoft To Do > Storage > Clear cacheThe app reloads cleanly and the connection error stops.If the app still says it cannot connect after these steps, the pattern matters. If one device works and another does not, the broken device likely has a local issue. If none of your devices can connect, the account or service is more likely at fault.
How to tell if it’s working again
You know the fix worked when your lists open normally, recent changes appear on more than one device, and the sync indicator stops spinning or failing. A good test is to create a small task on one device, then check whether it shows up on another device after a short wait.
If only some lists update, the problem is partly fixed but not gone. That usually means one of these is still true: the account on one device is different, one device is offline, or one app instance is holding stale data. Compare the account name on each device first, because that is the easiest thing to miss.
If a task appears on the web but not on your phone, the cloud copy is probably fine and the phone needs another local fix. If it appears on the phone but not on the web, refresh the browser, sign out and back in, and check that the web session is using the same account.
Why the problem keeps coming back
Repeat failures usually come from the same few causes. The most common is stale sign-in data: the app thinks you’re signed in, but the token it saved is no longer valid. Another common cause is background sync being limited by the device, so the app only updates when you open it.
Outdated apps can also keep reintroducing the same connection bug. If you fix it once and it returns after an update delay, check whether the app is current on every device you use.
Work and school accounts can make this harder. If your organization manages the account, a policy may block certain sync behavior or require a fresh sign-in after password changes, security updates, or device compliance checks. In that case, the problem is not just the To Do app; it may be the account rules behind it.
If you keep seeing the same error after changing networks, updating, and signing in again, the issue is probably not random. It usually means one device has a cached problem or the account itself needs attention.
When to stop troubleshooting and escalate
Stop local troubleshooting and look for a service or account issue if the problem appears on every device, the web version fails too, or sign-in breaks in other Microsoft apps as well. That pattern points away from your phone or PC and toward Microsoft’s service, your account, or an organization policy.
If you use a work or school account, contact your Microsoft 365 admin or IT team. They can check whether the account has been blocked, if permissions changed, or if a policy is preventing To Do from syncing.
If you use a personal account and Microsoft To Do won’t connect anywhere, try the web version from a different browser or device. If that also fails, the next step is account-level support rather than more device cleanup.
If only one device is affected after you’ve confirmed the account is correct, contact the device maker or app support route for that platform. The issue may be tied to that specific app install, browser profile, or operating system setting.
Conclusion
If Microsoft To Do still won’t connect, compare the devices that work with the ones that don’t. That tells you whether to keep working on the device, switch accounts, or wait for Microsoft to clear a service problem. If you want the quickest next check, test the web app and compare it with the device that fails.
Frequently Asked Questions
Why does Microsoft To Do keep asking me to sign in again?
That usually means the saved sign-in token is stale or the account session got interrupted. Sign out, close the app, reopen it, and sign in again with the same account you use on your other devices.
Can Microsoft To Do work offline?
You can often view items you already have on the device, but syncing needs a working connection. If you add or change tasks while offline, they may not reach your other devices until the app reconnects.
What if Microsoft To Do works on the web but not on my phone?
That usually points to a device issue on the phone, such as cached sign-in data, outdated app files, or restricted background syncing. Update the app, check date and time, and sign out and back in on the phone.