Maintenance of data in current client & not permitted

What causes this issue?

You have tried to call a table maintenance dialog for data which are
stored in another client. These data can not be maintained in the
current client.

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?

If you want to display the data, confirm the message with <PF>Enter</>.
Otherwise quit with <LS>Cancel</>.
If you want to maintain the data, log on in the client in which the data
are stored.

Error message extract from SAP system. Copyright SAP SE.