When attempting to change the scope of a list or library SmartObject to None, the following error appears:
"Thread 1: List does not exist. The page you selected contains a list that does not exist. It may have been deleted by another user."
This is caused by the deletion of a list or library without first deleting the K2 artifacts; leaving behind K2 artifacts for a list/library that no longer exists.
If you no longer wish to use a SmartObject/View/Form/Workflow, please delete these objects via the 'K2 Application' prior to deletion of the List/Library as per:
K2 Application > Delete All
Possible options to resolve this issue include:
A) Manually deleting all artifacts pertaining to this deleted list in the order below:
B) 1. Restore the list/library from the Site Settings > Site Collection Administration > Recycle Bin
2. Re-appify this list with the 'Create New Application' option; BUT select ONLY the 'Data Create SmartObject' option. This will re-appify the list and relink the objects; allowing for usage of the 'Delete All' option to delete K2 artifacts properly prior to the deletion of the actual list/library.