Every working mailbox handles attachments — PDFs from suppliers, invoices from HMRC, photographs from clients, CAD files from contractors. This tutorial covers viewing, downloading, adding and sharing attachments in SmartXHosting webmail, along with the size limits, supported file types, and security considerations UK businesses should keep in mind.
When a message contains attachments, an indicator appears on the message list (a paperclip icon) and inside the message header (a link reading "N attachment(s)").
To open the attachment list:
Each file shows as an entry you can tap to preview, download or forward.
Webmail previews common file types without downloading the file to your device first. Supported types for inline preview:
Inline preview is read-only — you cannot edit the file in the preview. To edit, download and open with your own application.
Microsoft Office files (DOCX, XLSX, PPTX), OpenDocument files (ODT, ODS) and archive files (ZIP, 7Z) require download, as webmail does not render them natively.
The filename is preserved from the original. If the sender used characters that your filesystem cannot handle (colons in Windows, or Unicode characters without proper encoding), your browser may sanitise the filename on save.
Desktop webmail supports bulk download as a ZIP archive:
attachments.zip containing every attachment.Useful when filing a client's correspondence — grab all attachments from a thread in one go rather than clicking each.
From the compose window:
You can attach multiple files in one go. Each file is uploaded to the compose window's draft; you will see an upload progress indicator. Only after all uploads finish can you send the message.
Removing an attachment: tap the X next to the file name in the compose window.
SmartXHosting webmail enforces these limits:
For larger files, use a file-sharing approach:
Other UK receivers' limits to remember:
| Receiver | Inbound attachment limit |
|---|---|
| Microsoft 365 / Outlook.com | 25 MB default, 150 MB for configured tenants |
| Gmail / Google Workspace | 25 MB; Drive link auto-inserted for larger |
| NHS.net | 20 MB default; exceptions possible |
| HMRC self-service portals | 10 MB per upload (for self-serve submissions) |
| Most UK SMEs on third-party providers | 10-25 MB typical |
If you send over 20 MB regularly, plan for the smallest denominator — target under 20 MB or use a share link.
Axigen accepts most file types as attachments but blocks known executable formats to prevent malware delivery:
Accepted: PDF, DOCX, XLSX, PPTX, ODT, ODS, TXT, CSV, JPG, PNG, GIF, WebP, MP4, MP3, ZIP (non-password-protected), RAR, 7Z, EPS, DWG, STEP, Blender, most engineering formats.
Blocked by default (inbound): .exe, .bat, .cmd, .com, .scr, .vbs, .js, .jse, .ws, .wsf, .msi, .msp, .hta, .cpl, .ps1, .reg, .jar, .lnk, .chm, .iso (sometimes), and ZIPs containing any of the above.
For legitimate cases where you need to exchange a blocked type internally, use a cloud share link or a zipped archive with a password (share the password via a different channel). Administrators can whitelist specific types per-domain if business need justifies it.
Q: Can I forward just one attachment from a message?
A: Yes. In the attachment list, use the share icon on the individual attachment — this composes a new message with only that file attached.
Q: Do attachments count towards my mailbox quota?
A: Yes. The inbox quota is the sum of all message bodies and attachments. Deleting large messages reclaims space after the Trash is emptied.
Q: Can I edit an Office document in webmail directly?
A: Not in webmail itself. Download, edit with your local application (Word, LibreOffice), and reply with the updated version attached.
Q: Why did my attachment fail to send?
A: Most common cause: exceeding 35 MB. Second most common: a blocked file type. Third: upload interruption during the compose session. Try again with a smaller file or via a cloud share link.
Q: Are attachments encrypted in transit?
A: Yes, inside the webmail-to-server channel (HTTPS) and on the server-to-server path where the receiving MTA supports TLS (most do). For guaranteed transport encryption with specific partners, implement MTA-STS or DANE.