HTTP Error 500.19 – Internal Server Error on identity server

In our QA environment, Sitecore login page is always navigating to ?fbc=1 and bypassing the identity server. When I hit the identity server url directly, it gave me 500.19 error (above screenshot).

First, I started checking the event logs for errors and troubleshooting. As I am having Sitecore version 10.2, so I checked for all the pre-requisite required for it to verify anything is missing.

After some troubleshooting, I figured out that there is problem with IIS support, .NET core, .NET core runtime and URL rewrite. So, installing latest version of .NET core windows hosting bundle and URL rewrite 2.1 resolved the issue.

For more information on HTTP Error 500.19, check out


How to fix – “A network-related or instance-specific error occurred while establishing a connection to SQL Server. The server was not found or was not accessible. Verify that the instance name is correct and that SQL Server is configured to allow remote connections. (provider: SQL Network Interfaces, error: 26 – Error Locating Server/Instance Specified)”

Recently I installed new Sitecore XP instance and when I have created tenant folder and tenant, I saw warning related to license on the top which says current license does not support SXA.

So I switched the license which supports SXA. And then yellow page with above error pops up.


Fix the certificate value in the connection string file in your wwroot folder. This has resolved the issue for me.

You can check for more insights into the issue and troubleshooting ways.