After installing Windows Updates on an Exchange 2016 server, OWA stopped working on one of my test servers. The error message "Server error in the /owa application" was displayed in the browser:
The event with the event ID 2001 could be seen in the event log of the server in question:
[Owa] Failed to load SSL certificate.
The event with the event ID 1309 was also triggered when trying to access OWA:
Apparently my IIS has "forgotten" its certificate after the update. In the site bindings of the "Default Web Site" in the IIS Manager, a certificate was no longer selected for both https bindings:
I have reassigned the correct certificate. Access is working again. Has anyone noticed anything similar after the last Windows updates? I will now install the latest Exchange CU 8 and see if there are any surprises.