I have read and followed through with the popular problem solving techniques for the all too common iaStor.sys issues.

I have my boot disc, everything goes as planned, I insert the 2 cmds

bootrec.exe/fixmbr

bootrec.exe/fixboot

into both c: and d: .
Both are received successfully. After this has happened, I restart and enter, the exact same problem.

The error I am told on screen is:

"If you have recently attached a device to this computer, such as a camera or portable music player, remove it and restart your computer. "

No amount of restarting or searching has yielded any results. Am getting fairly deterred by this time.

perhaps you have an old USB driver
go to device manager and search for a yellow sign, when found right click on it and uninstall, reboot pc and see if this helps.

or Use USB Oblivion
http://code.google.com/p/usboblivion/