Spooler: Some other internal error (RSPOEINTERN)

What causes this issue?

An internal problem has occurred. The spool system could not determine
the nature of the problem.

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?

Check the SAP system log for messages that may indicate the nature
of the problem.

Error message extract from SAP system. Copyright SAP SE.