ECP and OWA shows 500 error after patch update

[CUCOOPE]

Hi. Today in an exchange environment with DAG configured with 2 servers, EmailA and EmailB we have installed some patches on the two servers:

Update for Microsoft Windows (KB5010462)

Security Update for Microsoft Windows (KB5010419)

Update for Microsoft Windows (KB5008868)

After installing the patches, we have found that we cannot access ECP and OWA on EmailA (it shows error 500). One weird thing is, the CU22 (KB5007409) that we have installed on 11 Nov 2021 shows that it was installed on today as well in control panel.

We have followed the steps here but it didn't work. Everything works fine on EmailB so the impact was not that big.

We can re-install EmailA but we need some logs to show that the server has some errors through some logs. Can anyone help with the issue/or knows where can I find some related log files? Thanks.

[#2]

Did you try to run updateconfigfiles.ps1 and updatecas.ps1 ?
Sometimes after upgrade or update these scripts are not executed corretly and can also render EAC or ECP inaccessible, causing HTTP ERROR 500 after login.

These PowerShell scripts located in the Exchange Server ‘Bin’ directory (C:\Program Files\Microsoft\Exchange Server\V15\Bin\) to resolve the error. You can run from PS command line.