SAP GUI refuses file transfer

What causes this issue?

SAP GUI suppressed the file transfer.
This can be caused by the settings of SAP GUI or by declining the file
transfer via SAP GUI when the confirmation dialog appears.

System Response

The report stops processing and displays this message.

How to fix this error?

Accept the upload of files via SAP GUI when the confirmation dialog
appears.
OR:
Edit the SAP GUI settings to allow file transfers via SAP GUI

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.