Fortunately, fixing the PSP2UPDAT.PUP error is a relatively straightforward process. Here are the steps to follow:
use specific versions of this file (like version 3.65) to downgrade or reinstall firmware for homebrew compatibility. Common "Fixes" Involving This File psp2updatpup fixed
If the Vita cannot boot into the LiveArea (home screen), the system software must be "fixed" through Safe Mode. Users can use a USB drive with the folder structure PSVITA > UPDATE > PSVUPDAT.PUP on a PSTV, or use Fortunately, fixing the PSP2UPDAT
Ensure you are using the correct .PUP for your target firmware version. psp2updatpup fixed