This means that there was a bit of a communication problem between the proxy server and browser. There can be a large number of reasons for this, but they usually come down to some bad settings. I'm unfamiliar with Wingate, so you will need to search its documentation and even check any community forums for the program, to try and trace the problem.
hi
In my office i use windows XP for proxy server and workstations.
some times when i use firefox to explore the web, i receive the following error:
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Client error
dns lookup for XXXXX failed
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or, socket error
Note: XXXX is the url that i entered in the address bar.
i use wingate on XP as a proxy server. this transient problem some times occurs and disappears automatically.

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