Symptoms

K2 worklist App Part on existing K2 for SharePoint enabled SharePoint site collection is broken.

Recently infrastructure team updated the SharePoint security updates.

Clicking on the K2 app shows the error:
You are being redirected to the following url that was not registered as the app launch url .... If you trust this url, click here to proceed to the app now. Clicking click here fixing for only one time and it is asking every time refreshing or visiting the page. I rerun the K2 app registration wizard but not fixed.

 

Diagnoses

The following SharePoint updates where added:
- KB3114335
- KB3039768
- KB3114481
- KB3114733

One of the updates overwrote the app redirects.
 

Resolution

The client resolved the issue internally:
"I found the following in the ULS logs:

Check whether to allow CustomAppRedirect or not in the farm
SPFarm property CustomAppRedirect value is false or not set

So I added a "CustomAppRedirect" property to the farm:

(Get-SPFarm).propertiesi"CustomAppRedirect"] = $true
(Get-SPFarm).Update()"