Data recovery from a failed hard disk can be challenging, especially when emails are not backed up. Common methods discussed include using a USB docking station or caddy to access the drive externally, which has proven effective for many users. Software like File Scavenger has a high recovery rate, while alternatives like BartPE may also assist in data retrieval. In cases of mechanical failure, some suggest the "freezer trick" to temporarily restore functionality, particularly if the drive exhibits clicking noises. Users have noted that certain email servers may retain copies of emails, providing another potential recovery avenue. It's important to ensure regular backups, as many users have experienced data loss without adequate precautions.