UPDATE: Since this how-to was first written things have changed. Sony has released firmware 2.01 which makes this downgrade impossible. A PSP bricker trojan was released because of this antivirus software will classify both the good and bad downgrade files as harmful. You should do more research into the current state of the downgrade before attempting. As far as we know our firmware links are still good, we are not hosting them so we can not vouch for their safety.
C.K. Sample, III, TUAW / WIN Blogger and author of the forthcoming book, PSP Hacks, got his hands on the version 2.0 downgrader and wrote up a thorough how- to complete with pics for us. He even takes the extra steps to upgrade and downgrade yet again, just to make sure such a thing is possible.
As you can see, I have 2.0 running with the browser on my PSP. 
Step 1: Download the downgrader from either here, here or here. Then make sure you get a copy of the original 1.5 firmware upgrader. I found my copy here.
Step 2: Connect your PSP to your computer via USB. On your memory stick, create a folder called UPDATE inside /PSP/GAME/ and place the EBOOT.PBP file from the 1.50 update inside this UPDATE folder.
Step 3: Unzip MPHDowngrader.zip. Drop overflow.tif into your /PSP/PHOTO/ folder. Put both h.bin and index.dat in the root of your Memory Stick.
Step 4: Disconnect your PSP from your computer and plug in the AC adapter.
Step 5: Navigate to Photo then Memory Stick via the PSP’s menu system and start scrolling down through your photos until you reach the overflow.tif picture.
You’ll know you’ve hit it when everything freezes and you get a black screen with a bunch of white text output.
If your PSP freezes without going to this black text screen, then hold the power button for about 10 seconds until the PSP shuts down, then hit the power button again to start it back up. Repeat this step until you get that black screen.
Step 6: Don’t panic. Hold the power button for about 10 seconds until the PSP powers off. Hit the power button again. Your PSP will start up, and if you navigate to your System Information, you’ll discover that your PSP thinks it is running version 1.0 of the firmware. It isn’t and you cannot run homebrew (yet).
Step 7: Navigate to Game–>Memory Stick, hit the X button, and navigate to the 1.5 updater. Make sure you have your PSP plugged in or the upgrade won’t work. Click the X button and update like you normally would. At the end of the upgrade you will receive an error saying that the upgrade failed and to contact Sony. Don’t panic. Ignore this and again force your PSP to power off and reboot.
Step 8: After the PSP reboots you will receive an error screen that is scary and confusing because it is in multiple languages. Don’t panic. Find the language you can understand and read the corresponding line. It notes that your preferences are fragged and that you need only hit the O button to restore some default-ish settings. Hit the O button. 
Step 9: The PSP will start back up and you will go through the initial setup like the day when you first bought your PSP. Do so and then go to the system info pane again, where you will see that you are rocking version 1.5. Run homebrew at will.
I ran through this entire procedure, then I downloaded the 2.0 update and installed that again, and then yet again went through the entire procedure again. It works like a charm. It’s a little time-consuming, but you can have the best of both worlds. Have fun!
what chance does this have of working 50%? or what because i’ve spent lots of money on this an in my eyes it was wasted so allthough it cant run homebrew, i dont want it ruined all together. Can anyone help?
when downgrading, is it ok to use the 1.5 firmware off of a game that has the option to upgrade to it, or do u have to have the file on a memorystick?
It didnt work for me… I put everything in the memory card but when i goto click the picture file it freezes right after i click “Photo”
I’m getting Trojan.PSPBrick warning every time I try this. What’s up with that? Is it something I should worry about?
Damnit! I have Version 2.01. I mean damnit!!! Contact me when you find a way around this 2.01 block!
hello well i tried this downgrade with the information given to me above and it acutually worked. i was scared but i still did it just follow the instructions given above and it will be a success
i’ve downgraded to version 1.5 thanks for the help by the way the only thing is im badly missing the theme and wallpaper is there a way of getting these option’s back without having to upgrade higher than 1.5.
thanks for any advive you can give mark.
Can i make a sugestion. Cant you take a 1.5 update file and “rename” it to for example 2.5 then the PSP thinks that it is a new version and begins to update???
OH YEAH BABY! I kept getting the symantec virus error, so I decided to take a risk and disable it while i did this. Worked like a charm. Symantec probably got paid off by sony to say it was a virus.
How would you know if the downgrade had changed the mac address??
for example if the mac was 00:01:4A:AB:10:CD
would that be a valid mac..not that i use the web browser just dont like the idea of loosing functionallity.
downloaded yesterday worked great but i got a 512 memstick tried to downgrade again but psp cant finfd overflow tiff image on memstick whyyyyyy……. please help
Only download the downgrader files from here. There is a psp brick trojan but not in these files. I have copied this info from Symantec:
Trojan.PSPBrick arrives as an archive file named EXPLOIT 2.0 PSP Team V1.RAR which consists of the files overflow.tif and h.bin. Instructions call for the file h.bin to be placed in the root of a USB device and overflow.tif in the folder /PSP/PHOTO/. This archive may also contain a text file called PSPTEAM.NFO.
So if you see a downgrader from psp EXPLOIT 2.0 PSP Team leave well alone. Also I downgraded using the files and info from this site and it worked no problem.
hey i was wondering if i could delete the update and 100.bin, index.dat.bak, h.bin, index.dat, camarche.dat, and the overflow photo after i downgrade to 1.50. thanks : )
i think NOONE SHOULD DO THIS. HERE ME OUT, THE PSP IS FUN AND I HAD MY PSP SINCE AUG.6 2005, AND YOUR STUPID GAY RETARTED COCK SUCKING PROGRAM BROKE MY MOTHER FUCKING PSP! NOW IF YOU WOULD JUST TELL ME WHERE YOU LIVE, CREATOR GUY, I CAN COME KICK THE SHIT OUT OF YOU AND BEAT YOU WITH A GOLF CLUB! IM NOT SOME GAY NERD LIKE THE REST OF YOU WHO WRITE ON GAY-ASS FORUMS! IM GONNA MURDER YOU IF YOU CANT HELP MY PSP. I START IT UP AND THE LIGHT IS ON BUT I SEE NOTHING BUT BLACK! MY SYSTEM WAS 1.52
NOW HELP ME OR I WILL HACK YOUR SITE AND BLOW YOUR HDD! YOU WANT THAT TO HAPPEN? E-MAIL ME THE HELP AT GEOFFWK3@YAHOO.COM!!!!!!!!! BITCH!
I’m sure he’s running scared right now.
Read the directions again, did you miss anything? This has worked fine for a bunch of people.
“MY SYSTEM WAS 1.52” this is what he says… well I thought this was a “2.0 to 1.5 downgrade” tutorial… Am I missing something? Why would you downgrade when you don’t need to and when you don’t even have the firmware version that should be downgraded?
Hahahahahaha oh man I love angry people.
lol, “IM NOT SOME GAY NERD LIKE THE REST OF YOU WHO WRITE ON GAY-ASS FORUMS!” he said as he wrote on the forum. “NOW HELP ME OR I WILL HACK YOUR SITE AND BLOW YOUR HDD! YOU WANT THAT TO HAPPEN? ” wait I thought you where going to “KICK THE SHIT OUT OF YOU AND BEAT YOU WITH A GOLF CLUB!”, and I am confused If your so technologically unexperienced how are you going to perform such a feat? Ah well guess I am just a newb, maybe one day all understand your fluid coherent manner of thinking.
“Profanity is a feeble mind trying to forcibly express itself”.
You have serious anger management issues. Perhaps if you are covered by your states socialized medical plan you should consider seeking therapy.
yea i got the ver 2.01 for the psp so iam guessing iam screwed cause i wanted to put emulators is there anything i can do to play snes emulators again please help me
!!!!
haha dick
I know that guy, he couldnt hack for his life, hes a nerd wannabe, hes only 13 and he loves his PSP, haha its dead
#160 –
Here’s what you do to fix your PSP Brick.
DON’T HACK IF YOU DON’T KNOW WHAT YOU’RE DOING
I know it was a tough lesson, but most are.
On a side note, noone is no one, here me out is hear me out.
Learn to spell, it gives you more credibility.
Finally, I seriously doubt your so-called ‘hacking’ abilities.
Don’t threaten Hack-A-Day. Nobody listens to you, you gay nerd who *wrote on a forum.
I say good day sir!
i am terribly sorry to creator guy and forum people i was just mad and it was my fault… dont take in all that angry stuff!
SORRY!
i tried this three times back and fourth, worked fine, it was user issue that killed #160
sorry as i am your program helped some of my friends so i am EXTREMELY SORRY!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
My psp is 1.51 version, and I can’t find any website that has 2.0 version to be downloaded now. Do you guys know where I can find it.
Please Help!!!
Thanks worked perfectly first time
http://www.pspupdates.com has it
hi there tries to downgrade my 2.0 psp to 1.5 but the overflow file has a virus called trojan.pspbrick and this isn’t the first download thia has happened on, can any one help on getting the psp downgraded.thanks joe
Geof, you ass. I already emailed you about this but here goes. You have the intellegence equivalent to a slug that has been run over by a car thrice. You better hope to god you are “covered by your states socialized medical plan”
(thanks bill) and if not that you have a job so you can see a proffesional about your issues. I don’t know your story but that comment abuot us
“STUPID GAY RETARTED COCK SUCKING STUPID GAY RETARTED GEEKS” was blatantly offensive NOW BRING YOUR MENTAL HEALTH ISSUES TO SOMEPLACE ELSE!. and I assume you were wanting to upgrade, not downgrade geoff. You are so un-intelligent that you think that now downgrade can be of any use. so shut your mouth dumbass.
Use the link at the top of this guide worked for me
OMG!!! dude i love u. U R MY HERO!!!!!
Angry guy just wants you all to send hate to that email address. I garuntee it’s not really him.
Sorry if you were all smart and already figured this out; but some comments seem to have taken it at face value – which isn’t fair on the real owner of that email address. Thanks.
i got to the black screen and white numbers. then when i try to run the 1.5 eboot, it says data corrupted. Can somone please help me?
No. 180: RTFM
” Step 7: Navigate to Game
m yea i just tried this and it thinks its running version 1.50 but whenever i try to run homebrew it say “This game could not be started. (800200001)” please help.
I just wanna know that if i started the downgrading(i did it till the 1.5 upgrade), then if I want to restart the process again, it’s enough to run the 2.0 upgrade disc?
I just wanna know that if i started the downgrading(i did it till the 1.5 upgrade), then if I want to restart the process again, it’s enough to run the 2.0 upgrade disc?
help me. my psp always automaticly turns off. am i supposed to name my folder UPDATE or update pls help me
what means with this part ??(make sure you have
changed your background to frame_buffer.png)
works perfect thx xxx
NoOOOOOooOoO!!! IT bRICKED MY PSP!!!!
lol
jk….it works perfectly
i serouisly need help i dont get this! i am gettin lots of different stuff. i dont have the overflow.tif thing…and everything else.help please!!!
yea im confused about goin to game then memory stick. it keeps showing up as corrupted data. i made the UPDATE folder and put the unzipped and zipped EBOOT.PBP in there as well. any suggestions would be appreciated
Thanks. DOES THIS WORK WITH THE NEW PSP CERAMIC WHITE EDITION??? THANKS. NEED TO KNOW BEFORE I BUY IT.
Has anyone had any trouble with this where it has completely ruined your psp?? Cause im thinking about doing this but not sure
im kind of stupid when it comes to this geeky stuff but dont worry im not trying to offend ya in fact i wish i was a geek at all this cool stuff well anyways can anyone help me i dont know how to downgrade what does it meen on step two where it says UNZIP MPHDowngrader.zip
im kind of stupid when it comes to this geeky stuff but dont worry im not trying to offend ya in fact i wish i was a geek at all this cool stuff well anyways can anyone help me i dont know how to downgrade what does it meen on step two where it says UNZIP MPHDowngrader.zip
I’m trying to downgrade my version 2.01 to 1.50 but every time I copy the overflow.tif file.
When I go to the photo menu it said that I have a corrupt file What am I doing wrong ? Please advise