how can i solve it? PHP max_execution_time : 900s

how can i solve it?

PHP max_execution_time : 900s

Attempting to download remote file : http://http://inventivermagazine.com/3/snapshot-1453522700-160123-041820-e7ca3816.zip

Processing archive: snapshot-1453522700-160123-041820-e7ca3816.zip (0b)
Error: Manifest data not found in archive.
Snapshot import complete