Is it permissible to activate multiple accounts for different individuals on Bitcoin mining websites (such as terabox.me) with the aim of obtaining a percentage of their output, by paying the activation cost of their accounts and then withdrawing the amount paid from them?

A person registering on a single website with more than one account to obtain features or promotional prizes:

Either the website does not object to this, and there is no Sharia-related impediment in the transaction; in this case, there is no harm.

Or the website does not permit this, and the person does it by way of deception; this is not permissible, based on the Prophet’s (peace be upon him) saying: "Whoever cheats us is not of us," and "Deception and treachery are in the Fire." One must also be careful about the presence of any Sharia-related impediments in the transaction itself.