> But first, the basic cause of this issue is not the VPN per se. Google simply sees a large volume of traffic coming from a single IP address, with no way of knowing that it's a VPN. The same behaviour has been reported by students of large educational institutions, where there is a large volume of users trying to connect to Google Scholar through the institution's single public IP address. The reality that there are hundreds, thousands or perhaps hundreds of thousands of individual users behind an IP address is not known to Google. The VPN provider or institution's network keeps track of the individual users while presenting a single connection to Google. There may be a rogue user somewhere on the network, or it may simply be the sheer number of attempted connections that triggers the blocking, but the point is that it has gone past the point of a CAPTCHA. I guess it's similar to power load shedding on an electricity network.
> But first, the basic cause of this issue is not the VPN per se. Google simply sees a large volume of traffic coming from a single IP address, with no way of knowing that it's a VPN. The same behaviour has been reported by students of large educational institutions, where there is a large volume of users trying to connect to Google Scholar through the institution's single public IP address. The reality that there are hundreds, thousands or perhaps hundreds of thousands of individual users behind an IP address is not known to Google. The VPN provider or institution's network keeps track of the individual users while presenting a single connection to Google. There may be a rogue user somewhere on the network, or it may simply be the sheer number of attempted connections that triggers the blocking, but the point is that it has gone past the point of a CAPTCHA. I guess it's similar to power load shedding on an electricity network.