After some more testing I tried forming the url without using the google js lib like such:
https://accounts.google.com/o/oauth2/auth?scope=https://adwords.google.com/api/adwords/&response_type=code&access_type=offline&redirect_uri=MYURL&approval_prompt=force&client_id=MYID.apps.googleusercontent.com&hl=en&from_login=1&as=-13c0c43bd1da40fd&pli=1&authuser=1 This did not produce the 400 error and instead produced a "Request offline access" as expected. It seems the url being passed by the google gapi js library is incorrect in some way. The uri comming from gapi.authorize is: https://accounts.google.com/o/oauth2/auth?zt={Long string}&from_login=1&hl=en&as=704bfab0aac7a3eb&pli=1&authuser=0 -- -- =~=~=~=~=~=~=~=~=~=~=~=~=~=~=~=~=~=~=~=~=~=~=~=~ Also find us on our blog and discussion group: http://googleadsdeveloper.blogspot.com http://groups.google.com/group/adwords-api =~=~=~=~=~=~=~=~=~=~=~=~=~=~=~=~=~=~=~=~=~=~=~=~ You received this message because you are subscribed to the Google Groups "AdWords API Forum" group. To post to this group, send email to adwords-api@googlegroups.com To unsubscribe from this group, send email to adwords-api+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/adwords-api?hl=en --- You received this message because you are subscribed to the Google Groups "AdWords API Forum" group. To unsubscribe from this group and stop receiving emails from it, send an email to adwords-api+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/groups/opt_out.