This guide will provide extra-cautious precautions and tips for when you are either flashing the PSP or using applications that edit the "flash0" (i.e. internal, important files). None of these tips are required for a successful flash, but following all of these steps guarantee you won't end up with a paperweight. Remember, before flashing your PSP I recommend you read all of these tips.
I've compiled a list of tips for when flashing. If you have any to add, please post in this topic. (Note: They are in no particular order)
1. Format your Memory Stick. Formatting the memory stick before updating/flashing will ensure that nothing goes wrong with the files being read on the memory stick. Although upgrading without a formatted memory stick will most likely work, if you want to be extra-safe do this.
2. Use a larger-size Memory Stick (more than 32MB). As we have seen with some newer applications (e.g. Dark Alex's Downdater Test 0.5), they require more memory than 32MB because they might write files to the stick (logs, etc.). Unless you know for sure the flasher works with lower-size memory sticks, then I recommend a larger stick.
3. Use brand-name Memory Stick (Sandisk or Sony). I have noticed some things with my Lexar memory stick that is quite disturbing (it is not fake). First, the latest version of NesterJ (a NES emulator) does not load with this third-party memory stick. DGEN (a Sega Genesis emulator) has the same result. Second, when using it with SonicStage, the application gives me a writing error, resulting in a full reboot of my PC. After testing this with multiple computers, it is safe to say that these errors can only be resolved with SanDisk and Sony cards. I would never trust my Lexar stick when writing to the flash in any way. (Some people say that the problem I'm having is with my stick alone. Although its been replaced two times by the manufacturer, it still gives me these errors. If you experience errors similar to this I recommend a brand name.)
4. Always read the readme. They are called "readme" files for a reason! Certain applications may require special steps to load, or even special files in order to run. Whether it's on QJ's front page, or with the archive itself, it should be read.
5. Don't test the untested. A few unfortunate people bricked their PSP's when the first revision of the 2.5/2.6 downdater came out. To avoid this, make sure some well-known members (or the developer him/her self) have confirmed it working.
6. Know what you are doing. Use common sense!!! If the program says only use gameboots < 1MB, then don't try using a 10MB gameboot! Make sure you know what programs or applications you are using on your PSP. Don't just download a program from a random web site. All of the downloads from QJ.net are approved and will not harm your PSP (if you are following the instructions correctly).
7. Follow all normal precautions. When writing to the flash, make sure the PSP has 50% charge (for extra safety, > 75% will ensure you won't loose power), is plugged in, and the memory stick or power is not interrupted.
8. Use a custom firmware. This was was saved for last for a reason! If you did follow this guide in any order, this one would be last. Before installing follow all of the tips listed before this. Most all custom firmwares right now have a "recovery mode" that could potentially recover a bricked PSP. Don't know which custom firmware to install? Click here for a great guide from QJ.net.
9. Watch out for [fake] downgraders. There's always a risk of bricking while attempting to downgrade because they write to the flash. There is no 100% guarantee that they will flash correctly. To be sure you have a successful downgrade follow all instructions and be sure to read that readme! Also make sure you download from QJ.net, cause some "fake" downgraders actually brick the PSP!
I hope this helps some people scared to flash the PSP. The PSP has many possibilities that can be unleashed but doing so could result in a brick. Don't let that happen to you!
Have suggestions to make this guide better? Post here.
Guide by: Cobra2168
Revision: 0.5 (fixed spelling and added some tips suggested by users)