I had a running system with Miktex 2.9 and Biber as well as Texniccenter 1 on a W7 machine. Now I bought a new W7 machine and wanted to reproduce the system on this machine. I installed the same Texniccenter version and the latest Miktex 2.9.5105. I also downloaded Biber from here and moved it to
C:\Program Files (x86)\MiKTeX 2.9\miktex\bin.
I then exported the output profiles from my old Texniccenter Installation and imported them in the new one.
The problem now when compiling on exactly the same .tex-files (after having deleted all the stale AUX-files etc.): I don't get any errors, but a lot of warnings. Basically, all my references seem to be
Latex warning: citation 'oreilly_2005' on page 92 undefined on input line 201.
I also went into the Settings and Settings (Admin) of Miktex and "refreshed the FNDB", didn't help.
I don't understand what the problem is, as, apart from the new Miktex (and probably biber version), everything is the same as on the old machine.