Symptoms

Currently we are adding a new Sharepoint Online instance and hooking it up to work with K2. There is an already existing SharePoint 2010 Farm working with the K2 Server. When attempting to add the K2 App to a Sharepoint Online site and run through the registration wizard we encounter the following error when adding in the K2 URL:

"This version of the K2 for SharePoint App is only compatible with K2 for SharePoint RTM or later."
 

Diagnoses

We first needed to confirm that the correct version of the app was being used. This app was firstly acquired from the SharePoint store and could be the wrong version of the app. We manually added in the K2 for Sharepoint 4.6.9 app from the installation package and then confirmed the version number of the app as a 4.6.9 compatible version (4.4120.5.1). This documentation will guide you on manually adding the app to the app catalog in SharePoint Online:

http://help.k2.com/onlinehelp/k2forsharepoint/ICG/current/default.htm_Install_Topics/OnLine/ManuallyAddApp.htm?TocPath=Install|SharePoint%20Online%20Installation|_____3

After this we saw the same error when running through the registration wizard. We then ensured that all servers were open on the correct ports and firewall exceptions were enabled for the various ports that K2 would use on the Sharepoint Online server. Utilizing this KB (http://help.k2.com/kb001318_). Other useful Documentation for this installation scenario can be seen below:

http://help.k2.com/onlinehelp/k2forsharepoint/ICG/current/default.htm_Install_Topics/Before/SP_ReqO365.htm

http://help.k2.com/onlinehelp/k2forsharepoint/ICG/current/default.htm_Install_Topics/Before/SP_ReqMixture.htm?TocPath=Plan|_____3

We then checked the installed components of K2 to check and see if K2 for Sharepoint had been installed on the K2 server. There were no Sharepoint components installed. The SharePoint 2010 WFEs all had the 2010 components on them but in order for a Sharepoint 2013 on prem or online instance connect to the K2 server we will need to run through the K2 for Sharepoint installer on the K2 server to add the correct components.
 

Resolution

Running through the K2 for Sharepoint Setup.exe on the K2 server added in the correct components. Now when we go to run through the registration wizard on the Sharepoint Online site it will successfully complete. The app can now be successfully added to the SharePoint Online sites.