Not possible to determine a valid currency unit for ISO code &

What causes this issue?

The document cannot be processed because the system cannot determine a
currency for ISO code &V1&.

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?

INCLUDE NA_SYSADMIN1

Procedure for System Administrators

Check the currency in Customizing (general settings) and maintain it if
necessary.

Error message extract from SAP system. Copyright SAP SE.