This article was created in response to a support issue logged with K2. The content may include typographical errors and may be revised at any time without notice This article is not considered official documentation for K2 software and is provided "as is" with no warranties.
The K2 Management site will display a white box and any Smartforms runtime pages will load with an infinite spinner.
K2 Administrator will not be able to log into K2 Management and will be blocked from performing tasks, such as: adding permissions to workflows or creating service instances.
To resolve this behaviour you will need to review your TLS Configuration for the K2 Server and the client machine.
The IISCrypto tool can be used to enable and disable TLS configurations: IIS Crypto - Simple Tool to Disable Weak Ciphers
From a K2 perspective it is best practice to enable all version of TLS but this can be environment specific.
This external article can assist: SSL/TLS Best Practices for 2019