When you upload an image or document to your Mailpro account, the original filename is replaced by a unique random string before the file is saved. This is a deliberate, technical choice — not a bug — designed to keep your files reachable from every email client and to avoid accidental conflicts with other users.

In short: We rename to make filenames URL-safe and unique. Your file content is never modified.

Why we rename uploaded files

The new name strips spaces, accents and special characters that break links in some email clients, and it guarantees that two users uploading logo.png never overwrite each other. The fresh name also forces inbox providers to reload the latest version, and unpredictable URLs are harder for scrapers to guess.

How the new filename is built

Mailpro generates a short random identifier and keeps the original file extension (.jpg, .pdf, .png…) so the file is still recognised by browsers and email clients. The image still displays exactly as before in your campaign — only the URL changes.

Important: If you copy a hard-coded link to one of your files, do not change the random part of the URL. The renamed name is the address used for delivery.

Where to manage your files

You can review and reuse uploaded assets from the file library in your Mailpro account. For details on supported sizes and formats, see file sizes and extensions and images and files hosting.

Use the renamed URL as is

Always copy the link Mailpro returns after upload — do not edit the random part. Need a refresher? Read our guide on hosting images and files.

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