Update: And here it is – downgrading made even easier! Yes, that’s correct, easier than drag & drop! Simply connect your PSP via USB, turn up your speakers, and run this executable – no questions asked! A huge thanks to Xtrusion for this release as it’ll hopefully result in less problems.

Download: Easy 2.71 Downgrader

- source: xtrusion

Update: Quick bug fix update: “Fixed a bug that caused premature bricking if the hack to force the unassign/assign of the flash failed.”

The download link below has been updated.

Update: If you’re still running into difficulties, I suggest reading p0Wer’s forum thread which details the steps taken to downgrade any PSP (FW 2.71 & below). It may provide some useful insight towards where you’re going wrong. Also, you can fetch it in PDF form, right here.

And yes, I can confirm the downdater package below does in fact work; I’ve used it myself.

Another day, another dollar… And lets not fail to mention a 2.71 to 1.50 downgrader!

Renowned PSP developer Dark_AleX, along side with Mathieulh & Yoshi, have managed to successfully downgrade a non-TA-082 PSP running FW 2.71 – thanks to the recently discovered TIFF exploit! The process entails several steps [and precautions] which closely resemble the same procedure taken to downgrade 2.50/2.60. With that in mind, it’s probably safe to assume someone will take the liberty in creating an “Easy 2.71 -> 1.50 Downgrader.”

1. Copy the files inside MS_ROOT to the root of your memory stick.
2. Wait someone with 1.50 to pass you a folder called DOWNDATER and copy it to the root of your memstick.
3. It is recomended that you have the psp at more than 50% batteery and connected to AC
4. Go to the xmb photo viewer.

   At this point will one of the following things:

   • You’ll see a full red screen. This indicates that the downdater is doing its job. Wait for it to finish. When it finish it will crash on purpose. Restart your psp manually and you’ll probably have a 1.50 if nothing went wrong.
   • You don’t see the red screen. This indicates that the downdater code has not started to execute. (even if the memstick blinks(or no), it doesn’t matter! if the screen is not red, you can safely restart the psp at this point).

   This happen because of inestability in the tiff.
   Don’t worry, just restart the psp and keep trying until you reach the red screen of downdate.
   The downdater code is NEVER executed partially. It’s either executed totally or nothing.

   It depends of “luck” but usually the downdater will start to execute in a average of 1/10 times.
   Things that may increase the probabilities:

   - A fresh formatted memory stick.
   - A 32 MB memory stick (and fresh formatted)

REMEMBER: THIS DOES NOT WORK WITH TA-082 MOTHERBOARDS!

Much respect for NOPx86 for discovering the libtiff exploit; Fanjita, Skylark, and everyone else involved with this phenomenal breakthrough!

Download: 2.71 Downgrader (includes all necessary files)

As always… with any flash-related tool, USE AT YOUR OWN RISK – good luck!

- source: lan.st