Mac OS X 10.6 unmountable boot volume can pose a big problem for the user as he will not be able to launch the operating system on Mac. You are facing this problem because the the start up disk where the operating system is installed is not responding or is corrupted. The files in the drive may also get damaged so you need to first try to repair the Mac OS X for Mac OS X 10.6 unmountable boot volume error. If the problem is not solved by this way then you can use the disk utility to repair the disk or to format it. Then after you can install the operating system. Now you must be interested in recovering the data you have lost which you can recover from the time machine backup. When you have fixed Mac OS X 10.6 unmountable boot volume and the time machine is not working then you can use the Mac data recovery software to scan the Mac drive and then provide the list of files that can be selected and recovered. So download the software and use it now.