My emclient has been hacked. This person deleted all my storage files. Is there anyway of retrieving these

I think it is unlikely that the application has been hacked, but maybe your Windows has been hacked and your user profile files have been deleted. The eM Client database is stored at C:\Users_[username]_\AppData\Roaming\eM Client.

Depending on how your account was setup in eM Client, your messages could still be available on the server. Log in to your email account using the web interface for your provider. If the messages are still there, adding the account to eM Client, or any other email client, will resync the messages with your computer.

If the messages have been deleted from the server, which is also a possibility, and you had enabled the offline option in eM Client, then restoring from your most recent backup will be the only other option.