Storage system & does not exist

What causes this issue?

You have entered a content server which is not known in SAP ArchiveLink
Customizing.

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?

Enter a known content server, or as the system administrator extend the
Customizing settings. Check the function Content repositories:
<DS:TRAN.OAC0>Execute function</>

Error message extract from SAP system. Copyright SAP SE.