lots of factor for getting low success rate. number 1 is proxy as previous poster said. need atlest 10 private proxy to work well. then comes to comments. are you commenting like hey..good post..thanks blah blah? did you adjust scrapebox settings according to your pc and internet connection. anyone who use scrapebox firs time will get low success rate until you try to learn all the ins and out of scrapebox
are you using the fast poster? always use the slow poster for wordpress and fast poster for blog engine.. and if possible use private proxies...