How To Fix TR671 - Invalid transport layer &

SAP Error Message - Details

• Message type: E = Error

• Message class: TR - Change and Transport System

• Message number: 671

• Message text: Invalid transport layer &

What causes this issue?

This transport layer does not exist.
If you want to create this transport layer, proceed as follows:
Respond to the warnings with <PF>ENTER</>.
Enter it in the list of all existing systems, including the dummy
system with its standard transport layers.
Save your entries.
Now you can create the transport layer(s) by selecting it.

Error message extract from SAP system. Copyright SAP SE.