UW Digital ID (Personal Certificate) - Signing and Encrypting Documents (Windows)

This document will guide you through configuring your personal certificate to digitally sign documents on Windows.

Before Configuration

Before you start signing or encrypting documents, you should make sure that you have downloaded and installed your certificate.

 Download Instructions: 

 Installation Instructions:  UW Digital ID (Personal Certificate) - Installing My Certificate (Windows and Mac)


Encryption with a certificate is unavailable with Office.

Digitally Signing Office Documents

The screenshots here are from Office 2016, but the process and language is the same across all current versions of Office.

  1. Create your document, spreadsheet or presentation, make sure it is saved.

  2. When ready to digitally sign it, click the File tab from the top left of your screen, choose the Info tab from the left, click the Protect Document icon and choose Add a Digital Signature.

  3. If you haven't saved your document, a window will open asking you to save. Click Yes.

  4. Enter a Commitment Type and a Purpose for signing and click Sign.



    You will need to make sure that you are using your Comodo certificate to sign your documents. If the certificate you are using is not issued by Comodo, click Change and select your Comodo certificate.

  5. Click OK to return to your Office application. The document is now marked as final and you will not be able to edit the document unless you hit the Edit Anyway button. If you choose to edit the document after the signature has been applied, the signature will be removed.

Configuring Adobe Acrobat XI Pro

You will need to add the AddTrust External Root Certificate before you can validate digital signatures from UW Digital ID in PDF documents.

  1. Download the AddTrust External Root Certificate: AddTrustExternalCARoot.cer

  2. Open Adobe Acrobat XI Pro and go to Edit > Preferences.

  3. Navigate to Signatures in the left-hand sidebar, then click More... under Identities & Trusted Certificates.

  4. Navigate to Trusted Certificates and click Import.

  5. Click Browse and select the AddTrustExternalCARoot.cer file. Click Open.


  6. Select AddTrust External CA Root under Contacts, then the certificate under Certificates. Click Trust.

  7. Check Use this certificate as a trusted root and click OK.

  8. Click Import.

  9. Once you see the following screen, you've installed the AddTrust certificate and Adobe can now successfully validate your UW Digital ID.

Digitally Signing PDF Documents with Adobe Acrobat XI Pro

  1. Open the document you wish to sign.

  2. Click Sign in the upper right, then click Work with Certificates > Sign with Certificate.

  3. If you see this window, click Drag New Signature Rectangle.

  4. Drag an area on the document to apply your signature to.

  5. Select your UW Digital ID. Be sure to select the Digital ID issued by Comodo. Click Sign.

  6. Specify the location to save your signed PDF and click Save.

Encrypting PDF Documents with Adobe Acrobat XI Pro

  1. Open the document you wish to encrypt.

  2. Click Tools in the upper right, then click Protection > Encrypt > Encrypt with Certificate.

  3. If you see this window, click Yes.

  4. Click Next.

  5. Select your UW Digital ID, making sure to select the Comodo certificate. You can specify if you want to always use your selected Digital ID. Click OK.

  6. Click Next.

  7. Click Finish.

Encryption with a certificate is unavailable with Acrobat Reader DC.

Configuring Adobe Acrobat Reader DC

You will need to add the AddTrust External Root Certificate before you can validate digital signatures from UW Digital ID in PDF documents.

  1. Download the AddTrust External Root Certificate: AddTrustExternalCARoot.cer

  2. Open Adobe Acrobat Reader DC and go to Edit > Preferences.

  3. Navigate to Signatures in the left-hand sidebar, then click More... under Identities & Trusted Certificates.

  4. Navigate to Trusted Certificates and click Import.

  5. Click Browse and select the AddTrustExternalCARoot.cer file. Click Open.


  6. Select AddTrust External CA Root under Contacts, then the certificate under Certificates. Click Trust.

  7. Check Use this certificate as a trusted root and click OK.

  8. Click Import.

  9. Once you see the following screen, you've installed the AddTrust certificate and Adobe can now successfully validate your UW Digital ID.

Digitally Signing Adobe Reader Documents

  1. Open the document you wish to sign.

  2. Click Tools > Certificates > Digitally Sign

  3. If you see this window, click OK.

  4. Drag an area on your document to apply your signature to.

  5. Select your Digital ID to sign with. Be sure to select the certificate issued by Comodo.

  6. Click Sign.

  7. Specify the location to save your signed PDF and click Save.