AdSubtract does not properly handle complex form data, and SpamCop now uses a system which discards such invalid requests instead of trying to deal with them (done to combat denial of service attacks). This combination causes the "Network Error" problem.
AdSubtract users should configure their browsers to contact SpamCop's site without using the proxy server. Note, it is not sufficient to configure AdSubtract to allow spamcop.net. You must configure your browser to avoid AdSubtract.
One user reports this response from the makers of AdSubtract:
Response (Mike) - 07/24/2003 08:32 AM
Unfortunately sites like this require adsubtract not be present. We are aware of this issue, and hope to have it fixed in future releases of adsubtract.
Thank You
Another user reminds us it is necessary to re-enter the 'proxy ignore' settings every time you reboot the computer (at least with Windows XP). Rebooting causes the "ignore proxy for domain settings" to blank.
We (SpamCop) are working on a fix for this as well. More details will be posted here when available.
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