To restore lost files on a computer drive, make use of data recovery apps such as Restore My Files and Recuva. If you want to restore from a backup, use apps such as CrashPlan. Whereas Recover My Files and Recuva only work on Windows computers, CrashPlan is compatible with Macs and computers running Linux.
With Recover My Files, there are two main recovery options: Recover Files and Recover a Drive. If you lost files as a result of deletion, infection or corruption, click the Recover Files button, click Next, select the letter of the drive from which the files were lost, select Search for Deleted Files and click Start. Once the search is complete, check the search results for the files you lost. Tick each file you wish to recover, click Save Files, select the destination drive, and click OK to start the recovery process. If you lost files as a result of formatting or corruption of the hard drive, go to the Recover a Drive option instead.
To restore using CrashPlan, go to the Restore tab, select the destination you want to restore the files, and click Most Recent. Enter the date and time just prior to losing your files, select the folders you wish to restore, and click Restore.