SOLVED! “Microsoft Outlook Cannot Sign Or Encrypt This Message” Error: Troubleshooting

Many Microsoft Outlook users are reporting the error “Microsoft Outlook Cannot Sign Or Encrypt This Message.” 

If you are in the same situation and looking for easy ways to fix this error, you have come across the right page. This article will assist you in knowing the causes and fixes of the error. Thus, you can better come out from the issue and get back to work too. Remember, the given methods are tested, but we suggest you perform these only after taking a backup of files. This would not encounter any threat in the future. So, let’s go!

The Impact Of “Microsoft Outlook Cannot Sign Or Encrypt This Message” Error On Users.

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Microsoft Outlook is the most trusted platform in businesses. However, when someone encounter encrypts messages in the outlook, it fails the whole working process and sometimes indicates your unprofessional behavior to your clients. Thus, users feel irritated and want to let it off. Fortunately, we have rounded up some basic threats that can cause the “Microsoft Outlook Cannot Sign Or Encrypt This Message” error. So, go through this entire post and fix it soon.

What Causes “Microsoft Outlook Cannot Sign Or Encrypt This Message” Error? 

When a user tried to read its message online, users reported a Microsoft Outlook Cannot Sign Or Encrypt This Message” error because the message was encrypted. This message occurs due to reasons when MIME types are associated with the outlook web app policy, or you’re trying to send encrypted messages. Sometimes it causes because of the type of outlook account, be it 365, IMAP, or POP. Another cause behind the error is that missing certificates are missing for their clients. 

Now, let’s move on and know the easy troubleshooting steps to fix this error as soon as possible. 

How To Fix “Microsoft Outlook Cannot Sign Or Encrypt This Message” Error?

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After checking the causes, we have investigated the following methods to fix this error soon. So, have a look below.

Method 1- Add Digital Signature/Certificate In Outlook

In companies, it has been seen that many employees are unable to read their emails due to encryption errors. And it is just because they are missing a certificate, which everyone needed to read emails. 

So, to fix it, you have to install the certificates. Once it is installed, you will need to uncheck the digital signature for outgoing messages ad send a clear and signed message to your clients. Here’s how you can do this. 

  • Step 1: Start Microsoft outlook. 
  • Step 2: Click on the file option and choose the options command. 
  • Step 3: Then click on Trust center tab and jump to trust center settings. 
  • Step 4: Now click on the email security tab and uncheck the box that says “Add digital signature to outgoing messages.”
  • Step 5: Once done, save the changes or tap on the ok button. 

Now check, the error will be resolved. In case the issue persists, then read on next method. 

Method 2- Configure Server Settings

Sometimes this is an error of the server. It may be caused due to high traffic on time or if your servers are not updated for long. The below steps can help you configure the servers. 

  • Step 1: Start with the add new account option, configure the settings option, and jump on the next button. 
  • Step 2: Now, add the details of the server, including name, login information, etc. 
  • Step 3: Next, tap on more settings.
  • Step 4: Choose to configure SSL and TSL 
  • Step 5: Click on the OK button

Method 3- Sign-in with your Microsoft Account

If you see “Microsoft Outlook Cannot Sign Or Encrypt This Message” while accessing the email via Gmail or Yahoo. This message was sent to your Microsoft account. So, to fix the encryption issue, follow the given steps as under. 

  • Step 1: Open the email that sent you with the encrypted message
  • Step 2: When you open the email, you will find this error with an attachment “message.html .”Open it. 
  • Step 3: Click on Sign-in the email and check encrypted messages.
  • Step 4: Now, create an account option using your email. 
  • Step 5: Add all the required details.
  • Step 6: Verify your email address account.
  • Step 7: Once the verification is completed, open the encrypted message and read on.

Method 4- Encrypt All Outgoing Outlook Emails

If the error is still causing an issue, you have to enable the encrypt attachments and contents. 

  • Step 1: Start Microsoft Outlook and choose the tools option.
  • Step 2: Then select trust center and choose email security.
  • Step 3: Now check the encrypted attachments and contents of outgoing messages. 
  • Step 4: Tap on settings, change the additional settings, and click on the OK button.
  • Step 5: Tap on the ok button when the process is completed.

Method 5- Outlook Is Unable To Respond To The Proxy Server

Still, encountering the error? There will be an issue of poor internet connection or when the outlook is not responding to the proxy server. If this is your case, follow the steps given below.

  • Step 1: Connect your outlook with the RPC server to secure the outlook. 
  • Step 2: Now double-click the padlock icon, which is on the right side of a web browser. 
  • Step 3: Find the details on the details tab, including validity and subject.
  • Step 4: Now install the trusted root certificates by checking the certificate dialog box.
  • Step 5: Tap in the install certificate option then next. 
  • Step 6: Place all the certificates in the store box and then tap on browse.
  • Step 7: Now click on trusted root certification authorities and the ok button.

Now see the error is resolved. 

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Frequently Asked Questions

1\ Why am I receiving Microsoft Outlook encrypted error message? 

If the senders have the power to encrypt the message, it is sometimes an error of server and certificates. 

2/ How to unlock encrypted messages?

Open the email and enter the passcode to read the message.

Tips And Tricks

  • Check your internet connection
  • Fix the Proxy server issue
  • Update your server and outlook

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