Did you make a backup of the existing boot299.btl file? If not then the only recourse would be to reload a backup image toyour Tivo drive unless you can find another copy of the boot299.btl file. If you made a backup of the file and its still on the Tivo drive then you can install the drive in your PC, boot from any of the boot CDs or floppies (except the MFS Tools 2.0 CD), mount your partitions (see the Newbies Guide to the Tivo in the How Tos Only sticky in the DirecTV Tivo Hacking Forum for the procedure), and restore the backup file.
Please don't PM me or any other members looking for personal assistance. You'll do better by posting (after you've exhausted the search feature, of course) and taking advantage of the collective expertise of the membership instead of a single individual that may or may not be able to help you. Thank you and enjoy your stay at DDB!