Recently, one of my clients needed a new server.  This is a very small business with 5 PCs, so the version of server software chosen was WIndows SBS 2011 Essentials.  After migrating all of the Windows XP Pro machines, I set about to migrate the lone Windows 7 Pro machine and ran into an issue.  Hopefully, this will help anyone else out who runs into similar issues.

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The "correct" way to connect the client to the server is to hit the server (from the client) via web browser at http://server/connect. This will prompt you to download either the Windows version or the Mac version of the connector software. Saved this executable and ran it.  When it got to the point of entering the user name and password, I was given an error; "An unexpected error has occured".  Not too helpful.  Much Googling didn't turn up much and the error message as well as the online help topics were not very helpful.  I finally figured out the issue.

When trying to use the connector software to connect the client PC, you must make sure that the LAN connection is a trusted zone.  In my case, once the client PC was removed from the old domain, the LAN connection defaulted to "Public" which was blocking AD communications to the AD server.  After chaning this to a "Work" zone, the connector software ran without a hitch!