Hi, when i install Returnil, the free personal use version, there is already a serial number in the box and everything seems to install perfect. On reboot Returnil shows as registered. No matter how many times that i reboot, Returnil shows as registered . But whenever i shut the computer down, a blue screen shows with a couple of Returnil errors then the computer boots as normal. Once fully booted up, returnil shows as a trial version and if i try to start session lock, then a box pops up saying the device is not ready. I have to then re register with the serial, reboot and everything works fine, reboots and all until the computer has been shut down again. I have only used session lock. I have also tried to install with the VP and without the VP and exactly the same problem occurs. I am using Windows XP fully updated. Thank you.