Sorry for another bump but this is urgent for folks in here. OK, so thanks to this video....:
https://www.youtube.com/watch?v=dMZrozeKiIM
.....I was able to unbrick my slim 2001. By holding down Home, Select, Star, Square and Triangle while powering on I was able to resurrect my syste.
Wipes sweat from brow
6.61 Pro was not installed unlike what that message said and now my system firmware just says 6.60 as if it were set to official and my homebrew apps won't boot now.
Edit: OK, so now my system will only turn back on if I do the trick mentioned above. If I hard power off, the green power light will come on with no display or response and can only bring back the system again if hold down Home, Select, Star, Square and Triangle while powering on. So something messed up happened to my system since I installed that 6.61 file. Any thoughts? :/
FINAL EDIT: OK, reinstalled 6.60 Pro and everything is back to normal. Homebrew/emulators work again and my system reboots normally, what a relief. I'm just going to go to a friend's house and copy my new PS1 Classic purchases from his PS3's shop over to my PSP's memory card. My PSP shouldn't need 6.61 just to copy purchased PS1 games from a PS3, right?