Usually the pcapng (newer) or the pcap (legacy) format does the trick. After you believe the issue has been reproduced and/or captured, press the red Stop button and save the trace, which you can find under File > Save file as. The most basic way of starting a trace, is to select which network interface to start capturing from, and press Start. Please see Wikipedia for more information. This article assumes the reader has some basic knowledge of TCP/IP and the OSI-model, and network interface cards (NIC). This naturally gives a lot of information as a packet holds usually somewhere between bytes. While Fiddler intercepts traffic on level 7 of the OSI-model, the Application layer where HTTP is operating, WireShark can go all the way down to level 2 - Data Link, meaning it is able to analyze network traffic on a packet level. WireShark is a network analysis tool, much like Fiddler. It is written with the intention that the reader wants to know more about how to use WireShark for troubleshooting network and QlikView related issues. This article explains a few basic tests and features that can be useful for troubleshooting communication issues.

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