OUTLOOK attachments not clear on iphone - is it a storage issue?

Question

Our outlook email account was 90% full so I deleted alot of emails(thousands) and now outlook attachments are blurry when opening them on iphone for two people - any solutions? APp been reinstalled etc

Answer 1

Hi Dickson,

I understand that attachments have started appearing blurry in Outlook on two iPhones, even after many emails were deleted and the app was reinstalled.

Please note that this is a user-to-user forum, so contributors cannot access the accounts, devices, or Outlook mobile diagnostic information.

The Q&A Assist suggestion to check available iPhone storage is reasonable. Have you had a chance to check the free storage on both iPhones? However, mailbox capacity and iPhone storage are separate, and the information provided does not yet confirm that either is causing the blurry display.

I would like to add the following checks without repeating the steps already suggested:

1. Open one of the affected attachments, select Share, save it to the Files app, and then open the saved file directly from Files. Outlook for iOS supports saving an attachment to the iPhone this way.

• If the saved file is clear, the symptom is likely limited to Outlook’s attachment preview.
• If the saved file is also blurry, check the same attachment in Outlook on the web or ask the sender to confirm the original file quality.

1. In Outlook, open Settings, select the affected email account, and choose Reset Account. This refreshes the locally synchronized account data and is different from simply reinstalling the app.
2. If the attachment remains blurry only inside Outlook after resetting the account, contact Outlook mobile support from within the app through profile picture > ? > Contact Support. The in-app support route is appropriate because the support team can review Outlook mobile information that is unavailable in this public forum.

Please also confirm whether this affects every attachment type, such as PDF, Word, and images, or only image attachments, and whether the same files are clear when opened outside Outlook.

I hope these checks help determine whether the problem is with the original files or specifically with Outlook’s iPhone preview.

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Answer 2

Blurry attachments on iPhone can be related to storage pressure on the device, not just mailbox usage.

Try these steps:

1. Check free space on the iPhone:
   • Open Settings
   • Tap General
   • Tap iPhone Storage Microsoft recommends at least 1 GB of free storage for Outlook mobile to download updates and attachments reliably.
2. Free up device space if needed:
   • Save photos to a computer or cloud service, then remove local copies
   • Uninstall apps no longer used
   • Remove unused music or videos
3. Clean up mailbox storage further from Outlook.com on a desktop browser if possible. That provides the best cleanup experience, especially for finding and deleting the largest emails. On mobile, Outlook.com in a browser can also help identify large messages. In the Outlook app, filtering a folder by has attachments can help find messages with the biggest storage impact.
4. If the mailbox is still near quota, reduce it further:
   • In Outlook.com, go to Settings > Account > Storage
   • Review Email storage by folder
   • Delete large emails, especially messages with attachments
   • Empty Junk Email
   • Empty Deleted Items, because deleted mail still counts until that folder is cleared or items age out
5. Since the app was already reinstalled, also confirm the account is no longer hitting mailbox quota. A quota issue can affect Outlook mobile performance.

If the iPhone has enough free space and the mailbox is no longer near quota, the supported guidance in the available documentation is to continue cleanup through Outlook.com, because that is the recommended way to manage Outlook mobile storage-related issues.

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References:

• How much free space should my device have for the best experience?
• How can I free up space on my iOS device so Outlook and other apps can run more smoothly?
• What is the best way to manage storage in Outlook Mobile?
• What is Microsoft cloud storage?
• Mailbox Quota Exceeded