On the top right of the page, click the button that says Install Office.In a web browser, navigate to the Microsoft Office portal.Skype for Business is available from the Microsoft Office 365 website. Installing the Skype for Business App Instructions A Certificate Import Wizard will pop-up, click Yes, then click OK.Select Trusted Root Certification Authorities.Select Place All Certificates in the Following Store.Lawrence username and password if prompted. Click to download the Skype for Business Windows Certificate.Installing the Windows Certificate Instructions Once you have done that, you may then install the Skype for Business app and sign into it normally. Please note that Skype for Business comes pre-installed on all University Windows computers.īefore using the Skype for Business app on Windows, you must install the Skype for Business Windows Certificate in order to sign in with your St.