Symptoms:
When HTTP is enabled from Administration->Configuration, HTTPS will also start working for the Web Manager
When HTTP is disabled, Web Manager will load after a very long time
The user credentials will not work and may error out with “Invalid password for the user “admin”.

Analysis:
Essentially, this could be a case where the SSL certificates are not configured properly.
Review the configuration to check if the Private Keys and Public Keys are set up properly.
Private keys should be configured in the Server Keystore and the Public Keys (Root, Intermediate and Self certificates) should be configured on the truststore of the client.

Run the below command to check if the import of the certificates was successful:
keytool -list -v -keystore cis_studio_truststore_strong.jks -storepass changeit > output.txt

After reviewing this setup, it was observed that the public keys were not imported into the CIS Studio Truststore file

Run the below command to import the certificates:
keytool -import -alias ace_dv_virtual_etringer  -file "E:\Certificates\etringer.us.lmco.com.cer" -keystore cis_studio_truststore_strong.jks -storepass changeit -v

Restart the DV Server after importing the certificates.