Hard drive been re-partitioned? Files been deleted?
The Computer Professor can usually recover most of your data, depending on what exactly has happened. The most important thing is to stop using your computer as soon as possible, the longer you use it, the less likely it is that your data will be able to be recovered.
When a file is deleted, it is not actually removed from the hard drive. All that happens is the information telling the computer where to find it on the hard drive is erased and the position is then marked as free so that new data can be written to the same area. This is why your data can be recovered and why it is so important to stop using the affected hard drive as soon as you can.
As long as the hard drive still physically works then we have several possible ways to recover your data. If your hard drive no longer physically works then unfortunately we will not be able to help and you will need the services of a profesional data recovery company who have the necessary equipment to do this type of recovery.