Windows Data Recovery Software
This may be more information than is necessary, but I cant help myself its a compulsion when it comes to computers:
Since the pictures were on your computers hard drive, you need a Windows Data Recovery Software program to get them back. However, nothing is guaranteed here.
Everything on your hard drive is referenced for location, you see this as folders, subfolders, file names, etc. but your computer only knows it as a location code. When you click on delete, one of two things happens. If the file is too big it does not go to the recycle bin but is deleted emmediately. If the file fits in the recycle bin, its reference or location code is changed to show it as stored in the recycle bin. Think of it as changing folders from My Pictures to Recyle bin and moving all the pictures there.
If the file is too big and is deleted, or you empty the recycle bin, the computer does not actually delete the file. Instead, it removes the first part of the files name, hence removing the files location code or reference. Without the location code or reference, the computer cannot find it and therefore considers that part of the hard drive where the file was stored as empty even though it is not actually empty. Ie Windows just ignores it and feels free to write over it.
What the software does is search for the file based on the entire file name instead of just the reference or location code. Once found, it enable you to supply that first letter and thereby re-name the file to its original name and enable windows to recoginize the file again.
The only problem is, once Windows deletes that first letter it can at any time use that space to write another file to. For this reason, there is no guarantee that you can recover the file. The longer you wait between when it was deleted and when you try and recover it, the less you can recover as other files are likely to have been written over it.
Still, considering what was lost, I would consider it worth the effort to at least get a trial version of the software downloaded and see what it finds. Even if it finds only some of the lost pictures, well some is better than none. Also, look for recovery software that goes as far as three "layers" down when searching. This type of software can often look "under" new files to find the old files and actually restore them by moving them up into memory, giving them a valid name, and re-writing them on another spot on the hard drive. This type of software stands a better chance of finding and restoring files than the more commercial or cheaper software does. It is usually mostly automatic and therefore easier to use.
Good Luck and hope this helps.