These instructions will detail how to remove the K2 for SharePoint App and re-install the app back to SharePoint.
The primary purpose for these steps is to resolve this error:
"Your K2 server is running a newer version. Update the app and then run the Registration Wizard."
Please note that this process will not remove any of your K2 solutions. These are stored in the K2 database and they will return after the sites are activated again.
If you encounter any issues during this process, please reach out to K2 Support at Nintex
Second-Stage Recycle Bin: