Import Log of Idoc

Dear Experts,

Idoc is sent from X system to Y system. In X system idoc was processed successfully. However, in Y system getting following error,

Status 51 Application document not posted

Message IDoc was not posted; see import log

Can you please advice, how to see the import log in Y system? Tried SLG1 but no success.

Regards,

Amol Joshi