No special requirements for hardware or software.
If monitored computer can run Microsoft Windows 95/98/ME/NT/2000/XP operating systems, the Email Spy will run as well.
The computer on which you read the e-mails sent by Email Spy can be ANY computer, including Windows, Macintosh, Unix, Linux and Sun. The only requirement is that that secret email account must have sufficient Inbox storage space to receive all the emails from the monitored computer.