PDF won't open or is password protected: what to do

Sometimes the tool says a PDF is protected, or that it can’t open the file. This guide explains each case and what you can do. One rule applies to all of them: we don’t break passwords. If the document is yours and you know the password, there’s a simple path. If it isn’t, the password is there to protect whoever sent it.

“This PDF is protected by a password or against editing”

There are two kinds of protection:

• Password to open: the PDF reader asks for a password before showing anything. Banks, phone companies and stores often send statements and bills this way, and the email that brought the file usually explains what the password is.
• Editing lock: the PDF opens normally, but the author blocked changes, copying or printing.

In both cases, the tools here won’t open the file. We don’t try to guess or get around the protection.

The document is yours and you know the password

You can create a copy without the password, legitimately, with your own PDF reader:

1. Open the PDF in the reader on your computer or phone and type the password.
2. Use Print and, as the printer, choose Save as PDF (that’s the name in Chrome and on Windows; on a Mac, it’s under the PDF button in the print dialog; on iPhone, use Share, then Print, and open the preview to save).
3. The new PDF has no password. Use that file with the tools.

Keep the unprotected copy safe: it’s no longer locked. If you only need to send the document, ask the recipient first whether the password-protected PDF is fine.

You don’t know the password

Ask whoever sent the file for the password or for an unprotected copy. Don’t use programs that promise to “remove the password” from someone else’s document: besides being wrong, many of them are scams.

“We couldn’t open this file”

The file doesn’t look like a PDF, or it’s damaged. The most common causes:

• The download didn’t finish. The file is cut off. Download it again on a stable connection.
• It isn’t really a PDF. A file whose name ends in .pdf but is something else, like a web page saved with the wrong name. Open it in a PDF reader to check.
• An expired chat attachment. Ask the person to send it again.
• A very old PDF, or one made by a buggy program. Open it in a PDF reader and use Print > Save as PDF to create a fresh copy. That copy almost always opens with the tools.

Too many pages or out of memory

Everything here happens on your device, and each tool has a page limit so phones don’t freeze: 500 to merge, split and compress in light mode, 200 to organize, and 100 for PDF to JPG and strong compression. The maximum size is 50 MB per PDF.

If you hit a limit:

1. split the document into parts with split PDF;
2. do what you need with each part;
3. merge them again with merge PDF, if needed.

If you see “This device ran out of memory”, close other tabs and apps, or use a computer.

The digital signature is gone or invalid

A PDF signed with a digital certificate becomes invalid if the file is changed in any way: compressing, merging, rotating or removing pages. That’s how signatures work, not a bug. If the document needs its signature, send the original file without running it through any tool.

Your files stay with you

The tools run in your browser. A protected PDF is never sent anywhere, not even to try to open it: the check happens on your device, and the file stays with you.