Unable to access K2 application components such as K2 Designer, K2 Workspace or K2 Management with errors appearing.
kbt151117
PRODUCTIssue
You are unable to access K2 application components such as K2 Designer, K2 Workspace or K2 Management. This issue occurs due to the use of HTTP/2 in newer browsers, which has stricter requirements than HTTP/1.1. For more on HTTP/2, you can read the following Microsoft documentation: https://tools.ietf.org/html/rfc7540#page-5Symptoms
You will see the following errors:
"ERR_SPDY_INADEQUATE_TRANSPORT_SECURITY" when using Chrome.
"NS_ERROR_NET_INADEQUATE_SECURITY" in Firefox.
This often occurs with the use of Windows 2016.
Troubleshooting Steps
Although not a K2 issue, the errors caused by use of HTTP/2 can prevent usability of K2 components. Thus, this can be a crucial thing to check when coming across these types of errors.
This issue is primarily caused by incorrect ordering of blacklisted cipher suites. To re-order the cipher suites, you can download the IIS Crypto 2.0 tool here: https://www.nartac.com/Products/IISCrypto/Download
Once downloaded, you can refer to the following Microsoft documentation for steps on how to reorder blacklisted cipher suites to the bottom of your list: https://support.microsoft.com/en-us/help/4032720/how-to-deploy-custom-cipher-suite-ordering-in-windows-server-2016
You can find a complete list of blacklisted ciphers here: https://tools.ietf.org/html/rfc7540#appendix-A
