My FP4 migration is blocked using easy-installer

Hi @jlDessort welcome to the /e/ forum.

Perhaps best first to rule out, did you do your own “security patch verification” as described on the manual install page, Install /e/OS on a Fairphone FP4 - “FP4” ?

If Easy Installer is at fault … you might find the log and share it …

… or check out whether a manual install would not be easier.

However, fp4 is reported to have a fault in the install script affecting (some) Windows users, planned to be fixed in e-2.6, I think, later this month.