You know where to find the most important files on your PC - the documents, the pictures, the music - and they're always available when you need them. So it's easy to assume that's the way it will always be.
The reality can be very different, though. Maybe you're not paying attention for a moment and delete something accidentally, perhaps there's a software bug, or something happens to corrupt your hard drive: whatever it is, the end result is that you've lost files, folders, maybe even an entire partition of valuable data.
Don't panic, though - there's a good chance that your files are still intact, somewhere on the disc. And if you act quickly then you may be able to recover everything. All you'll need is reliable free undelete software to run a scan, and we've found ten free tools which can help.
Read on for our pick of the best free undelete software...

1. Recuva Free

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Conveniently available in a portable version, Recuva Free is very easy to use. A wizard asks you what type of files you're looking for, and where to search, then scans your system at speed (FAT, exFAT and NTFS file systems are supported).
Any files found are listed (with previews for images), and you can restore anything you need in a couple of clicks.

Running the program in Advanced Mode provides more options, though, like a Deep Scan (much slower, but recovers more files), the ability to locate files containing particular text, and even an option to securely wipe files containing sensitive information, ensuring that no-one else will be able to undelete them.
Whatever mode you're using, Recuva is an excellent recovery tool, effective and very easy to use.

2. Undelete 360

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Undelete 360 is the free version of a commercial product, and so leaves out some useful features (file filtering, previews and so on). These still appear in the interface, though, and suggest you upgrade if you ever click on them, which can be annoying.

Undelete 360
There are no restrictions on the amount or size of the files you can recover, though, and otherwise the program is very simple to use: point it at a drive, it'll scan for deleted files, then you can view particular file types (JPGs, PDFs, videos and more) by choosing them from a tree.
Scanning speed isn't great, but Undelete 360 can recover files that other programs miss , and so it's definitely worth considering.

3. MiniTool Partition Recovery

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Standard undelete programs are perfect for recovering a few files, but if you've lost an entire partition then you'll probably benefit from a specialist application like MiniTool Partition Recovery.
The free (for personal use) program has a wizard-based interface which makes it very straightforward to use.

MiniTool Partition Recovery
Point MiniTool Partition Recovery at the problem drive, specify the area to be searched, and it'll scan for the missing partition.
A report will let you know what the program has found, and you can recover the partition in a few seconds.
You don't get a bootable recovery disc here, so if your system partition is damaged then MiniTool Partition Recovery won't help you very much.
Otherwise, though, it provides a quick and easy way to locate and restore lost partitions.

4. Wise Data Recovery

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It's hard to imagine how any undelete tool could be simpler than Wise Data Recovery.
There are no menus, no complicated options or dialog boxes: all you do is choose a drive, click Scan, and wait as the program locates any deleted files.
Select what you need, click Recover, and that's just about it.

Wise Data Recovery
Wise Data Recovery doesn't seem to work with FAT-based drives, though, recovering nothing from our test USB drive. It's only free for personal use, too. But if you just need something quick and easy to recover files from NTFS drives then it should probably be on your shortlist.

5. PhotoRec

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PhotoRec is an extremely powerful undelete tool with very few restrictions.
It's free for everyone, runs almost everywhere (DOS, Windows, Linux, OS X, more), works with most file systems and device types, uses in-depth knowledge of more than 200 file formats to help recover your data, and the bundled TestDisk can even recover a deleted partition.

There is a complication, though: PhotoRec has an extremely basic DOS-like interface which is sure to intimidate many.
This doesn't make the program complicated - it walks you through every step - but the focus here is mostly on functionality, so if you're more interested in ease of use then we'd look elsewhere.

6. FreeUndelete

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FreeUndelete is aging, slow, free for personal use only, and didn't manage to retrieve anything from our FAT drive - not a good start.
Point the program at an NTFS drive, though, and the story is much different, with FreeUndelete locating all our missing files.

They're presented in a folder structure rather than a single list, making it easy to locate whatever you need, and they can then be restored in a click or two.
So while there are better undelete tools, you might want to keep a copy of FreeUndelete around, just in case your first choice doesn't recover something.

7. Paragon Rescue Kit Free

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If your PC has been trashed so badly that it won't boot at all, then any undelete tools you've installed previously will be useless. But Paragon Rescue Kit Free is different. It comes on an image which you burn to CD, and if disaster strikes then you just boot from the disc and go to work.

Paragon Rescue Kit Free
The program can recover a lost or deleted partition, for instance. The Boot Corrector can fix common boot problems and may be able to get your working again. But if not, Paragon's File Transfer Wizard helps transfer key files to another local drive, or burn them to CD or DVD. Overall it's a useful tool: grab a copy now, just in case.

8. Glary Undelete

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Another no-frills package, Glary Undelete takes a fairly basic approach to data recovery. There's really nothing to do beyond choosing a drive to scan, clicking Search, and waiting for the program to finish (although that might take a while, as it's slower than most).

Glary Undelete
The program does do a good job of recovering data, though, on both FAT and NTFS drives. And any files it finds are presented in both a single list and by folders, while you can also filter them by file type or name, making it generally easy to find what you need.
So while there's little in the way of extras here, Glary Undelete scores well on the fundamentals.

9. Pandora Recovery

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Unlike some of the competition, Pandora Recovery doesn't just present the files it finds in a single list.
You can also browse them in an Explorer-like folder view, or use an excellent search tool to filter them by file name, size, creation or "last modified" dates (so you could search for everything altered yesterday, for instance). Images can be previewed, too.

Pandora Recovery
Unfortunately file detection isn't always so reliable, particularly on FAT drives, and the program's quick scan didn't recover anything for us.
The more thorough Surface Scan mode did retrieve everything, though, so on balance we'd say Pandora Recovery is still worth a try.

10. PC Inspector File Recovery

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PC Inspector File Recovery did well in our tests, correctly locating the full set of missing files on both FAT and NTFS drives. These are clearly presented in a simple folder view, there's also a simple search dialog to help you locate files by name, and the program can then restore them to local or network drives.
Getting to this point may take a while, though, as the interface is a confusing mess of tabs (we'd recommend you experiment on a USB key or some other spare drive until you've figured it out).

PC Inspector File Recovery
It's a little odd that the program can preview files as text or a hex dump, but won't preview JPEGs. PC Inspector File Recovery deserves a look for its core engine, then, but you'll need some patience to take full advantage of it.