Digital Signatures

Digital Signatures

Hi everyone,

I was wondering if there is a way to digitally sign files, with signatures available in client Machine.

Imagine this scenario, i have a portal where several users can insert documents.

For those documents to be legitimate, there is a need to sign them with user's signature (like the one in Citizen Card).

But i don't want to oblige users to download a file, sign it and upload it again. I want them to have a way to sign the documents automatically, within the web app.

Have you ever done something like this?

I know there are ways to auto-sign documents using server certificates...but how to do it with client certificates?

Any suggestions? How do i have access to such signatures? is there any API for that purpose? Any Java applet that runs on client side?

Thank you in advance,

Best Regards,

Diogo C S Cordeiro

Hi Diogo,


I'm not sure if this is what you are looking for, but you can check this Microsoft article on how to add or remove a digital signature in Office documents



Tiago Simões

Hi Tiago,

I am looking for something that looks more like this :

I tried to use the smart card solution, but haven't managed to sign a document...It keeps saying that "cannot find the private key on the smart card"

When i do manage that, than it is time to try and integrate with Outsystems a similar solution for this.

Has anyone tried some similar solution?

Best Regards,

Diogo C S Cordeiro
Hi Diogo,

Did you find a solution for your problem?
I have the same need you had when you created this post:
- digitally sign a file with the citizen card

Hermínio Mira
The problem is that the key you are trying to sign on (the citizen card, smart card, etc.) is on the client side, while the Agile Platform does its work on the server side. You'll need to find a way to get access to the signing information through a Web app, which in all reality, should be impossible. Why? Because the last thing a Web browser should do is allow access to the user's certificates, keys, cards, etc., and the OS should block it as well.

Your best bet is to see if you can write a Java applet or ActiveX control (I know, not attractive options) and embed them in your application.

The alternative is to have the user upload them, sign them with a cert/key/etc. on the server, and allow the user to download them again.

Hi Diogo,

There is an API from

Let me know if this works.