- 1). Fix your mailbox.atr files using the program ICE ECC. This program can repair damaged files and prevent future damage. Download ICE ECC for free online and install it on your computer. Open the program and choose the type of files you want to repair, mailbox.atr files in this case. The program will scan for the files and repair them.
- 2). Download the program FileRestore Professional, a corruption repair program, for no cost. Install and open the program. Choose the hard drive from the drive selection menu; the program will search the drive for corrupted files and repair them, including your mailbox.atr files.
- 3). Fix your corrupted mailbox.atr files using the program Unstoppable Copier, which you can download for free. Once you have installed Unstoppable Copier, run the program. Choose the "C:/" drive as the location to be scanned; the program will locate the corrupted mailbox.atr and other corrupted files and repair the damage.
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