Many "cracks" are bundled with trojans or spyware that can steal your email credentials or encrypt your files (ransomware).

Instead of deleting, you can choose to move duplicates to a specific folder or mark them with a flag for manual review. Large Mailbox Support:

for what you consider a "duplicate" (e.g., same body text, same attachments)

: Cracked software cannot receive critical security patches, leaving your email environment vulnerable to exploits. Privacy Breaches

: If a cracked version fails or accidentally deletes unique emails instead of duplicates, you have no way to recover that data. The official MAPILab support team cannot help users with unauthorized versions.