Tutorial written by Black_Skull, translated by KoubaK, vb_master redid banner.

Introduction

What until couple of days ago, was just a rumor, has become reality, once again, thanks to Dark_AleX, Harleyg, and Mathieulh. This allows us to have 2.71 firmware, with the 1.50 firmware functions. Yes, Yes, you not seeing things. It seems that 1.50 firmware no longer have a future.

Precautions

Precautions
//The flasing is a delicate process, since we are going to format the flash memory(flash0) of the PSP and install a "new firmware", so make sure you battery is fully charged, and the AC adapter is connected to the PSP.

// DO IT AT YOUR OWN RISK!, neither BlackSkull for making this tutorial, Dark_Alex, Harleyg, and Mathieulh for creating this Custom Firmware or any other person will take responsibility for any failure resulting into a brick.

FAQ
1. You CAN NOT flash from any firmware higher than 1.50, you must start at 1.50. Do not do it on Devhooked 1.50, doing so will result in a brick. This means if you are on 2.xx you can not flash first without downgrading back to 1.50.

2. Your 1.50 flash does not have to be a clean one, the DATA.DXAR creater does not take files from the flash0, it makes new ones from update EBOOTs.

3. You can't use a 32 MB memory stick to make the DATA.DXAR, go out and buy a bigger one.

Downloads

//Dark_AleX's 2.71 SE-A-Packed by BlackSkull: http://www.sendspace.com/file/uqsvtl

Installing the Files

//Download the pack "Dark_AleX's 2.71SE-a- Packed by Black_Skull.rar", and un-rar the files to the ROOT of your Memory Stick (where PSP and MP_ROOT folders are).

//When asked, overwrite the PSP and the GAME folders.

Now, In the PSP, Go to GAMES > Memory Stick and start the SE UpdateMaker.
A bunch of white letters will come up.
Once it finish (takes about 3 or so minutes), It will return to the XMB, Connect the PSP to the USB port, and now a new file in PSP/GAME/SEUPDATEMAKER, named DATA.DXAR, should be there. Now make sure, to used THIS program that the MD5 checksum is the same as:
Code:
8E59FAAA97F526F8EC723D1B77700C2B

If it DOES match, copy the file DATA.DXAR to the directory "PSP/GAME/271SEFLASHER".
If it DOES NOT match, DO NOT CONTINUE, try remaking the DATA.DXAR.


Installing 2.71 SE-A

//TAKE OUT ANY UMD THAT IS IN THE DRIVE!!!

Connect the PSP to the USB port, and make sure your battery is at least 75% (100% recommended) and plug the AC adapter.
Start the application, named "2.71 SE flasher".
It will display some pink words, just press "X", and it will start flashing your psp, it will display a percentage.
When it finish, it will display "Done...rebooting..." , and will restart to a new firmware: 2.71 SE-A.
Now You can Format the Memory Stick.

Loading Homebrew in 2.71 SE

//To Load Homebrew, as you used to in 1.50, you should put the homebrew kexploited or not, in the directory PSP/GAME150 (this one you create), and viola, you're done.
**APPLICATIONS LIKE XFLASH, DO NOT WORK!**

//To Load Homebrew, made for HENC just place them in PSP/GAME.

Recovery Menu

You can start it, by pressing "R" while turning ON the PSP.
With this we can recover out PSP from a brick.

If what you want is to change the configuration, we go into the recovery menu, then configuration, and there you can enable or disable:

-Skip the logo of SCE , This disable the automatically loading of the UMD.

-Hide Corrupted Icons.

If your PSP has bricked, just power ON while pressing "R", and activate the menu toogle USB.
Now USB is activated, and now we can add the files included in the pack.

Just copy the folder "RECOVERY" in PSP/GAME, in which you will include a 1.50 firmware eboot, renamed to "UPDATE.PBP", and execute from the recovery menu.

And we will have a 1.50 totally functional.