Why are people instaling Windows 8? Why did you install Windows 8? It is not a full version, is not compatible to most computers or laptops, and is basically an iphone OS. It's also not to be used as a primary OS and there are very few drivers available for it. Windows 8 Preview was made available for techs to review its operability and not for the general user to replace their current operating system.
I bet you installed it because it is FREE!!! .Well that free OS has a time limt of about 4 to 6 months before it becomes unusable.
All your files are gone, all your data is gone, and all you got left is an OS that will disable itself in a few months.
You need to install the previous OS, use your Repair Disk to re-install, you know, the one you got with the laptop (PC) or the one that you created when you first got the PC.