Hi JSC;

Please drill into this link to adjust your bindings for both http and https(https://jeremythake.com/troubleshooting-sharepoint-2013-hosted-apps-on-premises-404-not-found-error-af3a3c82031e)

Should you find the above information useful kindly mark such as "Kudo and/or Accepted Solution".

Regards;

Widson.

Hello  @JSC,

You can actually just configure your settings.

From the artifacts page you can create, edit and delete parts of the K2 solution. The Tasks list is integrated with K2 and all aspects have been generated.This page is a K2-owned page that is surfaced in SharePoint via an iFrame. If you look at the URL you'll see something like https://app-6210f94db9d1e7.denallixapps.com/....

This URL indicates that SharePoint has given control over to the app registered with that domain. This is inherent to the SharePoint 2013 app model and is how the context switching occurs between SharePoint and a provider-hosted app such as K2 for SharePoint.

For more information about this, check the following link: http://help.k2.com/onlinehelp/k2forsharepoint/ICG/current/default.htm

Those two articles can also be helpful when configuring the environment for the app:
https://jeremythake.com/troubleshooting-sharepoint-2013-hosted-apps-on-premises-404-not-found-error-af3a3c82031e - for the common mistakes you can make during configuration.

https://technet.microsoft.com/en-us/library/fp161236.aspx - what Microsoft says about it.

Should you find the above information useful kindly mark as "Accepted Solution and/or Kudo", as this will assist other community members looking for related information.

Regards,
Beswick

sK2 will not accept any liability for any issues arising from actions taken in respect of the information provided by any forum member]

Hello again 

You need to do this on Sharepoint but if you encounter error like error 404 you need to go to IIS binding. 

Regards,

Beswick

Hi;

On your SP, I hope this formal documentation helps when preparing your SP (https://help.k2.com/onlinehelp/k2five/icg/5.1/default.htm#Prepare/SP/SP-Prep.htm)

Thank you;

Widson,