There may be a configuration issue, no network connection, or the software you are using is out of date (and has a bug).
The application that caused the error may need to be configured to match your brower's proxy settings, assuming you are using a proxy.
You may need to refer to the application's manual on how to access and set the proxy settings.
A proxy server is used to mediate connections between two or more computers to improve security and privacy over the network and in many cases, cache frequent data to speed operations.
Check if a newer version of the software is available, and if so, download and install the update.
Fix the network connection. Assuming the physical or wireless connection is working, have Windows attempt a repair:
For Windows 7:
For Windows Vista:
For Windows XP:
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