CDReader

CDReader is a tiny application you can use to verify files for errors. It's primarily designed to help you scan CDs and discover any unreadable files.

Portable tool with a file explorer

The entire program's wrapped in an .exe file, which you can save anywhere the disk or on a USB flash drive, and just double-click. It doesn't change settings in the Windows registry or create extra files on the HDD without your approval.

Scan drives or directories for unreadable files

It adopts a classical-looking interface made from a standard window with a built-in file navigator to easily track down a specific drive or directory to verify it for reading errors. For this operation, it's possible to use a big buffer.
On scan completion, CDReader reveals the total number of files and folders in the current location, along with the size and elapsed time. If it identifies any errors, it shows the full path of the problematic file, along with the error's position and description. For example, a file cannot be opened because it's currently being used by another process.

Common file explorer options

Other than its main functions, the program is equipped with basic file browser features. You can find out the name, size, type and time of last modification of each item in the current location, change the display mode (large or small icons, list, details), jump to another location using a drop-down list, go up one level or go to the last visited folder, as well as create new folders. The context menu of your default file explorer is borrowed.

Evaluation and conclusion

Unsurprisingly, it left a small footprint on system resources in our tests. It didn't trigger the operating system to hang, crash or prompt error messages.
Although it's an old app, it still works on recent Windows editions. To sum it up, CDReader facilitates a simple UI and options to check file reading errors, which can be seamlessly used by anyone.