How to Send Large Files Online Without Upload Failures: Limits, Resumable Uploads, and Security

Pick a service whose free size limit covers your file, then use resumable uploads so an interrupted transfer continues instead of restarting. SendBig, for example, advertises free transfers up to 30GB with resumable uploads for logged-in users, AES-256 encryption in transit and at rest, and optional password protection, expiry dates, and download caps. If your file is larger than the limit, split it into parts before uploading.

Match the file to the size limit

The first failure point is usually size, not the upload itself. Check the service's stated per-transfer limit before you start, and compare it to your actual file or folder size.

SendBig's stated free ceiling is 30GB per transfer. If you're sending video, that ceiling is the number to check first, since raw footage often exceeds it.

Use resumable uploads so a dropped connection doesn't cost you the whole transfer

A standard upload that fails at 90% usually starts over. Resumable uploads change that: the service tracks progress and lets you continue from the last completed point.

SendBig describes the flow this way:

1. Log in before uploading. Resumable uploads are described as a feature for logged-in (free PRO) users, so an anonymous upload may not get this protection.
2. Start the upload and let it run.
3. If your connection drops, your battery dies, or you shut down, come back later and log in again.
4. Any incomplete uploads appear first inside the upload card.
5. Select the same file on your computer for each incomplete upload and click resume. The upload continues from where it stopped.

The practical requirement: keep the original file unchanged and in the same place. If you rename, move, or edit it, the service may not be able to match it to the partial upload.

Choose how the recipient gets the file

Most large-file services offer two delivery paths, and they behave differently:

• Email delivery — you enter the recipient's address and the service sends them a download link. Good for one or a few known recipients.
• Shareable link — you get a URL you can post or send yourself, through a blog, chat, or social media. Good for many recipients or when you don't have their email.

SendBig's upload card includes fields for your email, the recipient's email, and a message, plus a shareable-link option. Decide which you need before uploading, because switching later may mean re-sending the link.

Set expiry and download limits before you send

These two settings control how long the file stays available and how many times it can be pulled down. SendBig lists both as options on a transfer, and states that files are automatically deleted from its servers once the transfer expires.

• Expiry date — set it long enough for the recipient to actually download. A link that dies in 24 hours is useless if they're away for the weekend.
• Maximum downloads — cap it if the file is sensitive, so a leaked link can't be used indefinitely.

If you need a longer expiry than the default, check whether that requires a paid tier before you rely on it.

Add protection for sensitive files

SendBig describes two layers you can add:

• Password protection — the recipient needs a password you set and share separately. SendBig describes this as adding end-to-end encryption, with the password known only to you.
• Encryption in transit and at rest — SendBig states files are encrypted with AES-256, transfers use SSL/TLS, and its servers are ISO 27001 certified.

For anything confidential, send the password through a different channel than the file link (e.g., link by email, password by message). That way a single intercepted message doesn't expose both.

Verify the transfer before it expires

Don't assume delivery. Before the expiry date passes:

1. Open the shareable link yourself, or ask the recipient to confirm, and complete a download.
2. Check the download counter if the service shows one, to confirm it hasn't hit the cap.
3. Confirm the recipient has the password if you set one.

Troubleshooting a stalled or failed upload

• Upload restarts from zero — you likely weren't logged in, so resumable upload wasn't active. Log in and retry.
• Resume button can't find the file — the original file was moved, renamed, or modified. Restore it to its original state and path.
• Upload stalls repeatedly — switch to a wired connection or a more stable network, and upload one large file at a time rather than several in parallel.
• Recipient can't download — the transfer may have expired or hit its download cap. Check both settings and re-send if needed.

The core decision is simple: confirm the size limit fits, log in so resumable uploads protect you against interruptions, and set expiry, download caps, and a password before you hit send.