If Tealeaf is deployed on IIS 10 on Windows Server 2016 and Portal URL is configured to use HTTPS, then accessing Portal through Chrome, Internet Explorer, or Edge causes an error. The error doesn’t occur if Portal is accessed using an HTTP URL. To resolve the issue, follow these steps to disable HTTP/2 on the server:

1. Start > Run and type regedit in the displayed box.
2. Navigate to the folder/path: HKEY_LOCAL_MACHINE\System\CurrentControlSet\Services\HTTP\Parameters
3. Under the Parameters folder, right-click in the right side pane, select New > DWORD (32-bit) value. Specify the value name as EnableHttp2Tls and set its value data to 0 (zero).
4. Repeat that to add another value named EnableHttp2Cleartext and its value data to 0.
5. Restart the machine.

For IIS 10 on Windows 2019, you can disable HTTP/2 through IIS itself by following the following steps:

1. Start IIS manager. In the left pane, go to the website under which the Portal virtual directory is added.
2. In the Actions column displayed in right pane, click Bindings.
3. While adding https port binding, select the check box for the Disable HTTP/2 parameter.
4. Save the change and perform an IIS reset.