I tried to login today using my blogger custom domain account, but I kept getting a 404 error. Here are the steps I tried using both Chrome and a Internet Explorer, both with cache and cookies cleared:
- Visit any Stackexchange site (SO, DIY, English, etc)
- Click login button and select More OpenID options
- Enter my custom domain into the box: http://blog.theg2.net
- Press login and browser is redirected to the blogger login page (as expected)
- Login with my blogger credentials
- Credentials are accepted, but browser is then redirected to a 404 error page.
Depending on the browser I was using the URL that it was directed to would appear different:
IE displayed: https://www.blogger.com/openid-login.do
Chrome displayed (redacted): https://www.blogger.com/loginz?d=%2Fopenid-confirm.g%3Fidentity%3Dhttp%253A%252F%252Fblog.theg2.net%252F%26realm%3Dhttp%253A%252F%252Fenglish.stackexchange.com%252Fusers%252Fauthenticate%252F%26openIdSetupToken%3Doidrp.identity%253Dhttp%25253A%25252F%25252Fblog.theg2.net%25252F%2526oidrp.return_to%253Dhttp%25253A%25252F%25252Fenglish.stackexchange.com%25252Fusers%25252Fauthenticate%25252F%25253Fs%25253D8820be50-xxxx-xxxx-xxxx-da58db477401%252526dnoa.userSuppliedIdentifier%25253Dblog.theg2.net%252526dnoa.op_endpoint%25253Dhttp%2525253A%2525252F%2525252Fwww.blogger.com%2525252Fopenid-server.g%252526dnoa.claimed_id%25253Dhttp%2525253A%2525252F%2525252Fblog.theg2.net%2525252F%2526oidrp.trust_root%253Dhttp%25253A%25252F%25252Fenglish.stackexchange.com%25252Fusers%25252Fauthenticate%25252F%2526oidrp.assoc_handle%253D&a=ALL&pli=1&auth=DQAAAHwxxxxxxxxx-xxxxxxxxxxxxxxxxxxxxxxx........
I also noticed that a new login option for "StackExchange Account" was listed. I tried entering in my email account, but it said there was no account associated with it. Update: See blog post about new StackExchange OpenID
UPDATE: I was finally able to login by adding a second OpenID to my account (a Google account or StackExchange ID) and then login using that OpenID. It appears either blogger changed their OpenID system and/or StackExchange is no longer comparable with blogger open id accounts. It also works if you login to http://blogger.com before trying to login to a StackExchange site (see answer below). Trying to login to StackExchange first using a blogger OpenID with custom domain still generates a 404 error.