I can't leave comments, and blogger won't keep me signed in, why!?

You have a problem with authentication, and with cookie filtering. First, try a different login procedure.

1. Login to Blogger using "www.blogger.com".

2. Do not check "Remember me".

If that does not help, try a second time..

1. Clear cache, cookies, and sessions (not just cache or cookies) - then restart the browser.

2. Login to Blogger using "www.blogger.com".

3. Do not check "Remember me".

Alternatively, enable "third party cookies". That's the best solution, overall.

Source : http://www.google.cf/support/forum/p/blogger/thread?tid=3115df39d8d4a613&hl=en

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