Fix Outlook App Not Downloading Attachments on Android & iPhone

If the Outlook app on your Android or iPhone won’t download attachments, the fix usually involves checking your internet connection, clearing the app’s cache, or updating the app itself. Below are the exact steps to resolve this issue on both platforms, along with common causes and preventive measures.

Why Attachments Fail to Download

Several factors can prevent attachments from downloading in the Outlook mobile app. The most common include:

Poor or unstable internet connection – A weak Wi-Fi or cellular signal can interrupt the download.
Outdated app version – Bugs in older versions are often fixed in updates.
Corrupted app cache – Temporary data can interfere with file downloads.
Insufficient storage space – Your device needs enough free space to save the file.
File size or type restrictions – Some attachments are too large or blocked by your email server.
Permissions not granted – The app may lack permission to access storage.

Fix Outlook App Not Downloading Attachments on Android

Follow these steps in order. Stop after each one and test if the attachment downloads.

Check your internet connection. Open a web page or stream a video. If it fails, switch between Wi-Fi and mobile data or restart your router.
Force-stop the Outlook app. Go to Settings > Apps > Outlook, tap “Force stop,� then reopen the app.
Clear the app cache. In the same app settings screen, tap “Storage & cache� and then “Clear cache.� This does not delete your emails or attachments.
Update Outlook. Open the Google Play Store, search for “Outlook,� and tap “Update� if available.
Check storage space. Go to Settings > Storage. If low, delete unused apps or files.
Grant storage permission. In app settings, tap “Permissions� and ensure “Storage� is allowed.
Re-add your account. Remove your email account from Outlook and add it again. This resets sync settings.

Fix Outlook App Not Downloading Attachments on iPhone (iOS)

For iPhone users, the steps are slightly different:

Check your connection. Toggle Airplane Mode on and off, or switch between Wi-Fi and cellular.
Force close Outlook. Swipe up from the bottom, find the Outlook card, and swipe it away. Reopen the app.
Update the app. Open the App Store, tap your profile icon, and scroll to see pending updates. Tap “Update� next to Outlook.
Check iPhone storage. Go to Settings > General > iPhone Storage. If Outlook shows a large “Documents & Data� size, consider offloading the app (which deletes the app but keeps its data) and reinstalling it.
Reset network settings. Go to Settings > General > Transfer or Reset iPhone > Reset > Reset Network Settings. This clears saved Wi-Fi passwords but often fixes download issues.
Remove and re-add the account. In Outlook, go to Settings (gear icon) > your account > Delete Account, then add it again.

What to Do If a Specific Attachment Won’t Download

Sometimes only one attachment fails. Try these targeted fixes:

Open the email in a browser. Use Outlook on the web (outlook.com) and download the attachment there.
Ask the sender to re-send. The file may have been corrupted during the original send.
Check the file type. Outlook blocks certain executable files (.exe, .bat) for security. If the sender renames the file, it may work.
Try a different network. Some corporate or public Wi-Fi networks block downloads from email services.

Common Misconceptions About Attachment Downloads

Many users believe that attachments are stored on their device after previewing. In reality, previewing a file in Outlook streams it from the server and does not save it locally. To actually store it, you must tap the download icon (usually a downward arrow) and then choose “Save to Files� (iPhone) or “Save to device� (Android). Also, attachments older than a certain period may be removed from the server by your email provider, making them impossible to download regardless of app settings.

Preventing Future Download Issues

To minimize problems with attachments in Outlook:

Keep the app updated automatically.
Regularly clear the cache (Android) or offload the app occasionally (iPhone).
Ensure your device has at least 500 MB of free space.
Use a stable Wi-Fi connection for large files.
Check if your email provider has a size limit (e.g., 25 MB for many providers). If an attachment is larger, it may be delivered via a link instead.

Frequently Asked Questions

Why does Outlook say “Download failed� on my iPhone?

This usually indicates a network interruption or a temporary server issue. Try downloading the attachment again after toggling Airplane Mode, or switch to a different Wi-Fi network. If the problem persists, restart your iPhone.

How do I save an attachment from Outlook to my Android phone?

Open the email, tap the attachment, then tap the download icon (downward arrow). After it downloads, tap the three-dot menu next to the file and choose “Save to device� or “Save to Drive.� The file will appear in your Downloads folder or the selected location.

Can I increase the attachment size limit in the Outlook app?

No, the limit is set by your email server (e.g., Microsoft 365 allows up to 150 MB, but many free providers cap at 25 MB). You cannot change this from the app. If you need to send larger files, use a cloud storage link instead.

Why do attachments download as “blob� files on Android?

This happens when the file’s MIME type is not recognized. Rename the file with the correct extension (e.g., .pdf, .docx) after downloading. To avoid this, try downloading via the Outlook web app or ask the sender to resend the file in a common format.

Does clearing the Outlook cache delete my emails?

No, clearing the cache only removes temporary files like images and thumbnails. Your emails and attachments remain on the server and will re-download when you open them. On Android, clearing “Storage� (not just cache) may remove some offline data, but your account can be re-synced.

General steps for current mainstream versions; menus can differ by device and version. See the disclaimer or report an error.

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