Hi sec sec, our working firewall is a bit more used Device is up : 0 day 13 hours 47 mins 18 sec Packet rate : 4144/s Throughput : 20701 Kbps Total active sessions : 7915 Active TCP sessions : 7104 Active UDP sessions : 781 Active ICMP sessions : 16 Our block page is customized, but in a very simple way. I suspect that there is a performance problem by blocking "dangerous" content. If the firewall dont has the time to block the first bytes, it will block in the course of the http session (which could be build by more than one tcp sessions). And so, a small part of the pdf file will reach the client, leading to an error message of the browser plugin. Assuming that the firewall cannot buffer a lot of bytes, it seems to be possible that the firewall recognize dangerous content after starting to deliver the content. But then it would be imho more correct to sending the block page instead of simply blocking the further content. Anyway, since we upgraded to 4.1.7, the problem seems to be mitigated or dead. I will continue with testing during the next days. regards Manfred
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