Fix Send to Kindle Errors

You're here because something broke. You tried to send a document to your Kindle and got an error — maybe the cryptic e999 internal error, maybe a silent failure where nothing showed up, maybe a bounce-back email. It's frustrating, especially when you just want to read. This guide walks through the most common problems and how to fix them. And if you're tired of troubleshooting Amazon's system, we'll show you a simpler way.

Check your Kindle email address

Go to Amazon > Manage Your Content and Devices > Preferences > Personal Document Settings. Your Kindle email looks like something@kindle.com. Make sure you're sending to this exact address — a single typo means your document disappears into the void.

Check your approved senders list

On the same Amazon page, scroll to 'Approved Personal Document E-mail List.' The email address you're sending from must be listed here. If it's not, Amazon silently rejects the document — no error, no bounce, nothing. Add the sender address and try again.

Check your file

Amazon accepts PDF, EPUB, DOCX, DOC, TXT, RTF, HTML, and images. Files must be under 50 MB via the Send to Kindle app or 15 MB via email. Password-protected PDFs, DRM files, and MOBI (discontinued in 2023) won't work. If your file is too large, try compressing it or splitting it into parts.

Make sure your Kindle is online

Your Kindle needs Wi-Fi to receive documents. Swipe down from the top of the screen and check the Wi-Fi icon. If you sent something while offline, it should arrive once you reconnect — but sometimes it takes 5-15 minutes. Try syncing manually: Settings > Sync My Kindle.

The e999 internal error

The e999 error is Amazon's generic 'something went wrong' message in the Send to Kindle service. It's not your fault — it's a server-side issue on Amazon's end. It shows up intermittently, and there's no reliable user-side fix. You can try again in a few minutes, try a different browser, or clear your cookies. But if it keeps happening, the problem is Amazon's infrastructure, not your file or settings. This error has been reported by users for years and Amazon hasn't acknowledged it publicly.

The approved sender list — the silent killer

This is the single most common reason Send to Kindle fails silently. Amazon requires every email address that sends documents to your Kindle to be on your approved list. If it's not, Amazon drops the document without telling you. No error, no bounce, no notification. You just wait and nothing arrives. It catches people every time — you set up a new service, forget to add its sender address, and wonder why nothing is working. If you use DropKind, the setup walkthrough handles this step for you and tells you exactly which address to add.

File format and size issues

Amazon quietly killed MOBI support in 2023 — if you're still converting EPUBs to MOBI, stop. EPUB is the standard now. Password-protected PDFs and DRM-locked files also fail silently. For the email-based Send to Kindle method, the 15 MB limit is strict — Amazon rejects anything larger without a clear error. If you're sending a large PDF, try compressing images or splitting it into chapters.

When to try an alternative

If you've checked everything above and it's still not working — or if you're just tired of managing approved sender lists, Kindle email addresses, and file size limits manually — that's exactly why DropKind exists. You upload a file or paste a link, and DropKind handles the delivery. It uses the same Kindle email infrastructure under the hood, but you set it up once during a guided walkthrough and never think about it again. If something goes wrong, you see a clear error message — not a cryptic e999 or a silent failure.

Frequently Asked Questions

What does the e999 Send to Kindle error mean?

It's a generic internal error on Amazon's servers. It's not caused by your file or account settings. The only fix is to wait and try again later. If it persists, try a different browser or the Send to Kindle desktop app instead of the web version.

Why did my document never arrive on my Kindle?

The most likely cause is a missing approved sender. Go to Amazon > Manage Your Content and Devices > Preferences > Personal Document Settings and make sure the sending email address is in your 'Approved Personal Document E-mail List.' Also confirm your Kindle is connected to Wi-Fi and try syncing manually.

What file formats does Kindle accept?

PDF, EPUB, DOCX, DOC, TXT, RTF, HTM, HTML, PNG, JPG, GIF, and BMP. MOBI is no longer accepted — Amazon dropped support in 2023. Password-protected PDFs and DRM-protected files will be rejected.

How long should I wait for a document to appear?

Most documents arrive within 1-5 minutes if your Kindle is on Wi-Fi. In some cases it can take up to 15 minutes, especially during peak times. If nothing has arrived after 15 minutes, check your approved sender list and Kindle email address.

Does DropKind have the same errors?

DropKind uses the same Kindle email system, so the same infrastructure limitations apply — 15 MB email limit, approved sender requirement, Wi-Fi needed on the Kindle. The difference is DropKind handles the complexity for you. The setup walkthrough ensures your approved sender list is configured correctly, and if a delivery fails, you get a clear status message — not a silent failure. Error messages include "File exceeds the 15 MB email limit," "Invalid Kindle email address," and "Delivery failed" with a reason.

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