Form & language & is not active or has errors

What causes this issue?

The form assigned to the document is not active.

System Response

The form will not be formatted.

How to fix this error?

Please check in the SAPscript form maintenance transaction and see
whether the form exists and, if this is the case, whether an active
version exists. An active version does not exist if you find the entry
<H>New</> in the status line of the form maintenance transaction.
If the form you selected does not exist, either assign a form that
already exists to your document, or create a new form which can be used
for your document once it has been generated.
You <H>activate a new form</> using the function <H>Generate</>.
It is also possible for an error to occur even if your form has the
status 'active'. This error message is the result of extended checks,
that were not available the last time that your form was activated. In
this case, please select the menu option Form -> Check -> Definition
and complete the actions specified in the resulting message.
A typical error: A text element in window ... does not contain a name.
In this case, display the text elements and ensure that each text
element (format column /E) has a name so that it can be addressed by
the print program. The default text element (at the beginning, no /E)
is addressed and processed automatically. Never enter /E without a name
following it.

Error message extract from SAP system. Copyright SAP SE.