I use the integrated Windows search in Windows 7 very much. After a while I’ve seen that something disabled the Windows Search service everytime I reboot my system. The solution is to remove the RapidBoot tool from Lenovo. This tool’s purpose is to optimize the system boot time. That’s a good idea to do that, but I don’t like the fact that it just disables the Windows Search service. Therefore I immediately removed this tool from my system.
See details about this tool at http://support.lenovo.com/en_US/downloads/detail.page?DocID=HT051827