Thank you for bringing this to our attention. To confirm, are you using the Adobe hosted server i.e. ftp2.omniture.com for FTP? Recently, we have implemented a Firewall IP rate limit for concurrent connections. We have set in place some restrictions, which may cause your IPs to be blocked by our Firewall rules when you hit a certain limit of concurrent connections. Could you please open a Client Care ticket by emailing firstname.lastname@example.org with details on the Target account name, FTP server credentils, file name and the public IPs (the IP from which you are connecting to the FTP service) so we can verify if your connections are indeed being affected/blocked by the Firewall. Please let me know if you have any questions!