Install the AssinaJá certificate app

To sign in AssinaJá with the digital certificate you already have on your computer — the Portuguese Bar Association’s, for example — you need two pieces: the AssinaJá certificate app and the AssinaJá extension in your browser. This page explains what they are, why they are needed and how to install them.

What it is

Two pieces that work together:

Piece	What it does
AssinaJá certificate app	A small program installed on your computer. It finds your certificates, shows you a confirmation window before every signature, and signs.
AssinaJá extension	An extension for Chrome, Edge or Firefox. It is the bridge between the AssinaJá signing page and the app.

On Windows, the app appears in the list of installed apps as AssinaJá Certificados. The extension has the same name in the browser’s store.

What it is for

One thing only: signing AssinaJá documents with a Local Digital Certificate — the digital certificate that is yours, installed in Windows, kept in a .p12 or .pfx file, or on a card connected to the computer.

You only need it if someone sends you a document to sign with Local Digital Certificate. To sign with Chave Móvel Digital or a drawn signature, you do not need to install anything.

Why it is needed

A browser on its own cannot use the certificates installed on your computer. This is a security decision by the browsers themselves: a web page has no access to the system’s certificates. That is why people who sign PDFs with the Bar Association certificate use Acrobat, not the browser.

The app solves this without opening the door to anything else:

• Your certificate’s key never leaves the computer. AssinaJá sends the app only the document’s digest (hash); the app signs that digest and returns the signature.
• The app never sees the document, nor addresses, nor your AssinaJá sign-in details — only the digest, the document name and the address of the site asking for the signature.
• The file password or card PIN is only asked for in a window of the app, never on the page.
• It only signs for AssinaJá. The app and the extension refuse requests from any other site.
• Nothing is signed without your confirmation. Before every signature a window of the app opens — Sign with your certificate — showing the address asking for the signature, the document name, the certificate and the issuer. The button selected by default is Cancel.

Read the window before pressing Sign

The confirmation window ends with:

Only sign if you asked for this signature on AssinaJá.

If the window appears when you did not ask for a signature, or shows a document you do not recognise, press Cancel.

What you need

• Windows 10 or later, 64-bit (x64).
• Google Chrome, Microsoft Edge or Mozilla Firefox.
• You do not need to be an administrator of the computer. The installation is for your own Windows user only.

macOS and Linux

For now the app is available for Windows only. Versions for macOS and Linux are coming soon.

Install on Windows

1. Download the installer

Open the Software page on the AssinaJá website and download the Windows installer. The file is called assinaja-webid-win-x64.msi.

2. Run the installer

1. Open your Downloads folder and double-click the .msi file.
2. Follow the installer through to the end.

You are not asked for an administrator password. The app is installed in your user folder, in %LOCALAPPDATA%\Programs\AssinaJa\WebId\, and registered with all three browsers — Chrome, Edge and Firefox — at once.

3. Install the extension in your browser

Install the AssinaJá Certificados extension from your browser’s store:

Browser	Where
Google Chrome	Chrome Web Store
Microsoft Edge	Microsoft Edge Add-ons
Mozilla Firefox	Firefox Add-ons

In Firefox, make sure the extension is allowed to run on the AssinaJá sites. If it is not, the extension icon says:

The extension is not allowed to run on the AssinaJá sites.

Press Allow on the AssinaJá sites.

4. Check that everything is connected

Click the AssinaJá extension icon in the browser toolbar. You should see:

AssinaJá application connected

with the app’s Version below it. If you see “The AssinaJá application is not installed”, go back to step 2 and then press Check connection.

5. Go back to the document

If you were in the middle of signing, go back to the document page and press Search again. The Certificate step now lists the certificates installed on your computer — see Sign with your own digital certificate.

Update

When a new version comes out, download the new installer and run it over the old one: it replaces the installed version.

If the installed version is too old, the signing wizard tells you:

The AssinaJá app needs to be updated

Uninstall

Open Windows Settings, then Apps, find AssinaJá Certificados and choose Uninstall. This removes the app and its registration with the browsers. The extension is removed separately, in the browser itself.

If it does not work

The signing wizard always says what is missing. The messages you may see in the Certificate step:

Message	What to do
The AssinaJá extension is missing from this browser	Install the extension (step 3) and press Search again. In Firefox, also check the permission on the AssinaJá sites.
The AssinaJá app is missing from this computer	The extension is installed but the app is not. Do steps 1 and 2 and press Search again.
The AssinaJá app needs to be updated	Install the latest version and press Search again.
Could not talk to the AssinaJá app	Close and reopen the browser, then press Search again. If it keeps happening, reinstall the app.
The AssinaJá app does not recognise this address	The app only signs for AssinaJá addresses. Open the document from the link in the invitation email.
This page is not on a secure connection	The same: open the document from the invitation link.
Signing with a digital certificate is not possible on this device	You are on a phone or tablet. Open the document on the computer where your certificate is.

Related

• Sign with your own digital certificate
• Signature levels