Wireshark-users: [Wireshark-users] Pcap file isn't a capture file in a format TShark understands

From: kahou lei <kahou82@xxxxxxxxx>
Date: Thu, 21 Jan 2010 16:43:42 -0800
Hi,

I am using an EL3 machine and would like to translate some pcap files into pdml format. However, when I type this command:

tshark -r udp.pcap -T pdml >temp.pdml

I got this error:

tshark: The file "udp.pcap" isn't a capture file in a format TShark understands.

I also try

tcpdump -r udp.pcap

and I got this error:

tcpdump: bad dump file format

Looks like I have an invalid file format.

Can someone please advice what I should do in order to fix this?

Thanks,
Kahou