I had a windows 7 ultimate 32-bit on my laptop(NTFS file system) but according to some problems I formatted the drives and reinstalled the windows.Now all my PDF and CHM books gone. Which software can i use to recover them in the best way?
Firstly, stop using the harddisk. The more you use the disk, the more likely you are to overwrite the data you are looking for.
Then get a tool such as Active Undelete, it will attempt to find files that are still on the harddisk, but not visible to you.
But the main thing is to use you harddrive AS LITTLE AS POSSIBLE, until you have a suitable tool.