According to Microsoft there was an accidental update that installed a workstation update for Microsoft Root Certificate and applied this update to some servers.

To correct this issue follow this Microsoft Knowledgebase article, SSL/TLS communication problems after you install KB 931125 to remove the incorrect update, reboot your server, and run Windows Updates again to get the correct Microsoft Root Certificates.

Blackbaud is unable to address this issue because it is related to third-party software. For assistance, contact the third-party vendor.