Incorrect Header Checksum


All of the computers on a network I was troubleshooting SOMETIMES display “page cannot be found” in the browser when any website it accessed. When I tried to duplicate the problem, I just kept on opening IE windows and had set as a home page. The error message was consistent, but sometimes I could duplicate it in the second browser, and sometimes in third.
Installed Wireshark and tried to see what was really going on behind the scenes . For every page” can not be found” error I was getting “Header checksum: 0x0000 [incorrect, should be 0x35a9]” in the packets descant to the google’s IP address.
Questions: Is this a Transport Layer problem ?
What would be the next step in troubleshooting?

Thank you very much!