Node is not executable

What causes this issue?

You tried to execute a node (in the background). However, this is not
possible for all nodes. Executable nodes are displayed in color in the
tree (--> color key). Only the following nodes are executable:
Reports
Variants
Saved lists
The following can be executed in the background:
ABAP Reports and Queries with a variant (in this case, position the
cursor on a variant).

System Response

The system issues an error message and will not allow you to continue with this transaction until the error is resolved.

How to fix this error?

Error message extract from SAP system. Copyright SAP SE.