Wireshark: Trying to find the cause of the error

"The specified network name is no longer available"

We have an application that gives this error message to the users when trying to communicate to our SQL server.

I ran a wireshark capture, and found a lot of errors, especially ones with BAD Header checksum.

Can anyone spot anything wrong in this packet capture?

3251      14:40:55.117761000      10.192.219.7      10.192.220.7      TCP      1434      [TCP segment of a reassembled PDU]

3252      14:40:55.117784000      10.192.220.7      10.192.219.7      TCP      54      63934 > ms-sql-s [ACK] Seq=832 Ack=576761 Win=131072 Len=0

3253      14:40:55.117823000      10.192.219.7      10.192.220.7      TCP      1434      [TCP segment of a reassembled PDU]

Our SQL IP Addr is: 10.192.219.7, and when I filter on ip.dst == 10.192.219.7. For the most part I see things like:

3812      14:40:55.163537000      10.192.220.7      10.192.219.7      TCP      204      [TCP segment of a reassembled PDU]

Internet Protocol Version 4, Src: 10.192.220.7 (10.192.220.7), Dst: 10.192.219.7 (10.192.219.7)

Header checksum: 0x0000 [incorrect, should be 0xf7f2 (may be caused by "IP checksum offload"?)]

Bad: True

Expert Info (Error/Checksum): Bad checksum
LVL 8
pzozulkaAsked:
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dipopoCommented:
Could you disable checksum offloading on wireshark then try again.

Edit > Preferences > + Protocols .... disable Validate the x Checksum if possible in UDP, TCP and IP
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Network Analysis

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