Start page &1 not found.

What causes this issue?

You tried to start processing of the document with a different start
page than the standard start page. However, start page &V1& is unknown.

System Response

The system issues an error message.

How to fix this error?

Check the name of the start page.

Procedure for System Administrators

The system issues an error message and will not allow you to continue with this transaction until the error is resolved.

Error message extract from SAP system. Copyright SAP SE.