
Hello Mohamed DOUMA,
Litigation hold and retention policies can help you recover and restore deleted emails or OneDrive files from eDiscovery search in Microsoft 365.
Litigation hold is a feature that allows you to preserve all mailbox content, including deleted items, for a specified time. When you place a mailbox on litigation hold, all things, including deleted items, are preserved and cannot be permanently deleted by the user. You can use eDiscovery search to search for and recover deleted items from the mailbox. A litigation hold is typically used in legal or regulatory situations where you must preserve all mailbox content for a specified period.
On the other hand, Retention policies allow you to retain content for a specified time based on specific criteria, such as the age of the item or the folder it's in. When a retention policy is applied to a mailbox or OneDrive account, items that meet the retention criteria are retained for the specified time and cannot be permanently deleted by the user. This means you can use eDiscovery search to search for and recover items that meet the retention criteria. Retention policies are typically used to help organizations comply with legal or regulatory requirements or to retain essential business records.
Litigation hold is the best solution if you need to preserve all mailbox content, including deleted items, for a specified time. If you need to retain content based on specific criteria, such as the age of the item or the folder it's in, retention policies are the best solution.
I hope this helps. Please let us know if you have any further questions.