I'm working on a managed account on my iMac. For some reason, Gmail (or any Google sign-in for that matter) will not open on any managed account. I have reset keychains, used Keychain First Aid, reinstalled keychains from my Mac OS X disk, repaired disk permissions, and changed my DNS to Open DNS and then Google DNS to no avail. This is only a problem unique to Gmail. Originally, all SSL (https) sites would not work (i.e. Facebook), but after I repaired disk permissions, every other SSL site was fixed. This issue also occurs in Firefox. Parental Controls are on, but there are no restrictions on website visitation. I've tried turning Parental Controls off, but it still doesn't fix the problem. The only account that Gmail works on is the original admin account. In short, Gmail doesn't work, and I'm stumped. I have an iMac 3.06 GHz Intel Core 2 Duo with Mac OS X (10.6.4).