3 vr 5 nh 8 h cd 9 7 acid corrupted message courier mail server 0 47 hrwl com cn received following message delivery address message contains several internal formatting errors often caused viruses attempt infect remote systems instead blocking message converted safe text attachment safely read text editor sometimes also happens sender mail software bug creates improperly formatted messages although kinds formatting errors may often ignored mail servers server detects intercepts improperly coded messages order prevent viruses taking advantage bugs e mail programs headers message contain improperly formatted binary content see information