Hi,
ple check the below log,
http://www.saptechies.com/http-errors-in-xi/ - HTTP errors in PI.
Path sap/xi/engine not active
• HTTP 403 during cache refresh of the adapter framework - Refer SAP Note -751856
• Because of Inactive Services in ICF –Go to SICF transaction and activate the services. Refer SAP Note -517484
Regards
srinivas