Check the message and connection
- Confirm the message fully loaded and the internet connection is stable.
- Ask the sender to verify the attachment opens from their Sent folder.
- Check whether the file exceeds the provider or device size limit.
Try a safe alternate path
- Use the official webmail instead of an outdated desktop app.
- Try another supported browser after disabling only clearly identified problem extensions.
- Save to a folder you can access and confirm the device has free storage.
Respect security blocks
- Do not rename an executable file to bypass a mail filter.
- Scan unexpected attachments and verify the sender independently.
- Use an approved cloud sharing service for legitimate files that mail systems reject.
Stop guessing when the problem keeps coming back
Ask for help when all attachments fail, a business security policy blocks required files, or the message may be malicious.