Is it possible to re-add a deleted device?

Unfortunately, the answer is no. Once a device is deleted from your Prey account, all its information is gone for good for security reasons.

The only way to "re-add" a device to your list is to install Prey back on it, which can't be done remotely. You will need to have the device in your hand and install the agent again. However, you won't be able to recover any of the reports from the previous device entry.