FTP to file server - file not reached to file server but in XI success

FTP to file server - file not reached to file server but in XI success
Scenario is

XI is picking file from SAP and sending to a file server. In XI ,communication channel and sxi_moni shows message transferred successfully.

But the file server guys din't receive any file. Can any one tell where the message can be lost. If file is not reaching destination then how come in XI its showing SUCCESSFUL message.

Open the receiver file channel in channel monitoring in RWB and click on the message ID of processed messages.
You can see the audit log there where it mentions the FTP server and path to which the file has been delivered.
Confirm these details with file server team.
Check out the audit log for the message in MDT

Also reconfirm the target location(Server,Directory).
Your communication channel is not able to connect with the FTP sever.

Check in RWB the communication channel log also user id, password mentioned in communication channel.

Check whether that user has authorization to create file on FTP sever.
Receiver CC itself is stopped polling. Receiver Comm channel is not polling since last 5 days.
You can Select the Communication Channel Monitoring in the RWB and you can restart communication channel again,
here you will also find the SAP UserID who has stopped the CC.

Restar the comm channel and resend the messages probably it will work.

I think this is the way XI works when dealing with EO(IO) messages ... Once msgs have been delegated to the AFW, they are flagged as successfully processed from an IE perspective. But if you look at the MDT tool, you should see your (failed) msgs being either retried or set to an error status (ie, FAILED, NOT DELIVERED) !

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