Google Captcha

In the experience of the community what causes the “Unusual traffic” messages when doing google searches? This ISP network hands out public IP addresses to each and every customer. No batting going on. Does Google typically drop entire /24’s into this if they see an issue? The initial troubleshooting we have done involves disconnecting the customer router and going direct with a laptop. Still the same captcha. We clock “I am not a robot” and the search goes through, but it re-appaers the next search. Looking for a direction to look. What typically causes this? I know what the page says, but looking for specifics. Thanks Justin Wilson j2sw@mtin.net www.mtin.net www.midwest-ix.com