Using Let's Encrypt certificates in Windows IIS web server

[Angus Robertson 650]

If you are using ICS created Let's Encrypt certificates in Windows IIS web server, you may find web sites no longer work correctly, giving a certificate error.  

 

This is because Let's Encrypt had discontinued it's OCSP service as a means of determining if certificates have been revoked.  

 

In each IIS site bindings, for each listener, you need to tick 'Disable OCSP Stapling', and the certificates should work again.  

 

Happened here after a reboot for patch Tuesday.  I did not see any OCSP errors or warning in the IIS or Windows event logs, but knew about OCSP being abandoned. 

 

I've already added conditionals to the next ICS release to remove our OCSP code.  

 

Angus

 

Edited Tuesday at 06:42 PM by Angus Robertson