I mostly use my iMac, system OSX 10.7.5 with the latest version of Safari. I contacted Ancestry at least 2 or 3 months ago to ask what was going on. The tech told me that it was a Safari problem and that I needed to trash the cache and it wouldn't be a problem. Well, I've done that several times, I've erased my "history", I tried using FireFox instead of Safari...nope...I still get logged out on a very regular basis. Some nights every time I do a search, I have to sign in...every time. I will even completely shut down my computer, restart and try again....same thing. Other days/nights I can get through almost all my searches without a problem. Tonight has been one of the bad times...I do more signing in than researching. HELP US ANCESTRY.COM!!! I have the iPhone app, but that's too difficult to use for actual researching...just to check on info.