I really need your help.
I use netbootin to create a bootable Backtrack 4 USB thumbdrive (4GB).
I booted from the USB and did the following:
I then deleted the first four partition
Then I created the first partition with +1500M
Then I created the second partition.
Then I set the partition type for the first partition to vfat and that of the second to linux
I format the partitions.
I then shutdown backtrack.
The next day I tried to boot windows. It says: "This is not a bootable disk. Please insert a bootable disk and press any key to continue."
I only remembered fiddling with the files on the thumbdrive. I admit that I dunno what I am doing. Did I delete my files on Windows? If so, what should I do? How can I get back my files on Windows?
Try going into your system with a LiveCD, such as ubuntu and see if it can recognise your Windows OS partition via nautilus file manager. Otherwise, it doesn't look too good.
If you only deleted the partition and didn't install BT or something afterward, then you still might be able to recover all your data. I'd boot up in a recovery disc with partition recovery software of some kind. Never used any linux recovery apps so I can't tell you what a good one would be, but I'm sure someone here or on a general linux forum could.