I have a new laptop, a toshiba p870, that came with windows 8 preloaded. I needed windows 7 for compatibility reasons with a few programs and after a bit of research and struggle I eventually got it installed on a second hard drive in the computer but in the process I had to change the bios settings to disable secure boot and enable CSM. After that Windows 8 will no longer boot even if the second hard drive with windows 7 is removed. I have no way to access the bios in order to change this setting back, the only way to access it was by going through the windows 8 recovery and troubleshooting settings, inserting a windows 8 disc (from a previous installation on a different computer, non-uefi) didn't offer the uefi firmware options in recovery mode. What can I do to restore access to windows 8 on this system?
EDIT: I finally figured it out. You must hold shift as the computer shuts down in order to get the toshiba logo and the option to enter the bios with F2 to show up at startup. This isn't a very convenient setup for dual boot, having to change between CSM and UEFI to choose operating systems but it works.
Could you get us a picture of the Disk Management window to include the graphical partition info. Maybe it will help us see what is going on. You can use the snipping tool to take the picture and then attach on the Advanced replies.