I was on vacation part of the weekend and this week out of town. I decide to bring my laptop and the 436hp with me. Saturday I turn on laptop and sentinel will not open it says can't open or send error message ( send the error). I rebooted the computer and tried again samething. Than I uninstalled it and rebooted computer and downloaded the software and load it and same problem. I am running win7 pro with 8 gig of ram.