How to Fix Skype Certificate Error?

Being one of the most used video calling applications across the globe, Skype has been helping people to communicate with each other for so many years. However, there are certain errors that might pop up while using this application. Skype Certificate error is one such error. 

This one mainly appears when you want to login to skype. This error occurs when there’s something wrong with the Skype server, Lync.

As this error is displayed on the screen, you won’t be able to login to the Lync. This error means that there is some problem with the server. When Lync goes for acquiring the personal certification for the login purpose. 

Well, here in this post, you will get to know all the possible solutions to solve the problem with your Skype application.

Reasons Behind Skype Certificate Error

To get rid of Skype Certificate Error, you have to first understand the causes behind this error. It is found that this error occurs mainly due to these following reasons:

  • In most cases, it occurs due to the outdated Lync client program.
  • If you use an outdated version of Microsoft Online Service, then you can face the problem.
  • It can also occur when a client does not get a skype certificate.
  • This error can also occur when there is a malware or virus attack on the system. 

Solutions to Fix Skype Certificate Error

Now, as you have become familiar with the reasons behind this error.  Let’s discuss the methods for solving it.

Step-1: Erasing the Sign-In Information

This is the first step you should follow while facing this error. When the stored sign-in information has some issues, you may face this issue. To solve this issue, you can undergo these steps:

  • At first, you have to open the ‘Skype for Business’ window and then click on the ‘Delete my sign-in’ option.
  • As you have pressed on the delete option, your saved connection settings, certificates, and passwords will be deleted from your device.
  • In the end, re-enter your information again and hopefully, your problem will be solved.

Step-2: Downloading of the certificate

If your PC screen displays a message which says that there is a difficulty in signing in skype for business purpose. Then there might be an issue with the personal certificate, important for using Skype. To install the certificate, you have to follow these steps:

  • First, visit the Skype official website and download the certificate.
  • Double-click on the file you downloaded for the installation process.
  • Now, as the installation window appears on the screen, click on the Open button. Choose the ‘General’ tab in the Certificate Window.
  • Tap on the ‘Install Certificate Button’ and mention whether you want it for all users or only for the current user. After making the right choice accordingly, click on the ‘Next’ option.
  • As the next window appears, go to the ‘Place All Certificates’ option and tap on the ‘Browse’ button.
  • Search for the folder of ‘Trusted Root Certification Authorities’ and then put the file inside that folder.
  • Next, you have to choose the location and tap on the ‘Next’ button. Lastly, click on the ‘Finish’ option for the completion of the whole process.

As you have completed the above process, the system will automatically get restart.

Step-3: Flushing of DNS Cache

Sometimes, flushing the DNS cache can help you a lot in recovering you from the problem. 

  • Open the Command Prompt (Admin) from your Windows 10 device by pressing the Win + X keys together. 
  • As the Command Prompt opens, type in the following line of command and hit the Enter key.

    ipconfig /flushdns

Wait till the above process gets over and then close the Command Prompt and check if you are still encountering the error. 

Step-4: Make Changes With the Help of Registry Editor

If the above solutions didn’t help you, then use the Registry Editor and make some changes in it. 

  • First, press the Win +R key from your keyboard. Then, you have to type ‘regedit’ and hit the ‘Enter’ button for opening the Registry Editor.
  • In the next step, follow the register path. You have to go to,


  • After that, click on the ‘MachineGuid’ option. If you find any value such as a list of numbers and some letters inside the brackets, then delete it.

At last, you have to close the ‘Register Editor’ and then you have to try to sign in to skype.

Step-5: Clearing of Lync’s Cache

This is the easiest method to solve Skype Certificate error. For doing this, undergo the following steps:

  • Firstly, your device has to be turned on. Then, you have to erase the Session Initiation Protocol folder.
  • Secondly, all the files have to be deleted but remember not to delete any folder from that location.
  • Open the Registry Editor again and erase the folder of a specific user’s expandable sip profile.

So, with the help of the above-mentioned methods, you can easily delete all the Lync cache data.

According to your needs, you can follow any step and resolve the Skype Certificate Error. But even after following the above steps, if your problem is not resolved, then feel free to share your experience using the comment section.