So this seems like same or very similar problem to the one at: http://boards.ancestry.com/thread.aspx?m=6690&p=topics.s...
The error message we get is "Authentication with the server failed". But the result is that the web search doesn't work or anything else in FTM that needs a web connection. And it thinks you aren't logged in or registered or have a subscription to Ancestry.com. And won't let you log in or register (re-register), etc. And your problem has been going on since February??????
And some people had same or very similar problems in 2008 based on another thread named the same "Authentication with the server failed" that was started in Nov. 2008 and last post to it (until last week )was Nov. 2010.
Yikes this is worst then I thought!!!!!