logged in on back-end but not front-end!

[aetherdesign]

Hi,
This is not a Genesis issue, but I was wondering if anyone has had this problem...
When I am logged into my site as administrator I can use my back-end as normal, but the front-end does not recognize that I am logged in. (the admin bar does not show up and I cannot view my site in maintenance mode) **This is happening in firefox, chrome and safari, but not in internet explorer, and it is happening on multiple computers. Also, I have several other wordpress sites and none of them are having this issue.
I have tried re-installing wordpress, changing themes and disabling plugins, all to no avail.
Any ideas??
sellingdcrealestate.com

Thank you!