@GutsNaem
Ok I found the solution I post it here if anyone needs it in the future :
It's all my bad the Names where not in lowercase, and even if the uppercase does work without external datastorage it doesn't when using an USB Storage.

Hello everyone and sorry to bother you.
Before taling about the problem I precise that I followed the guide to use external datastorage for Roms and that I put BIOS files both in the recalbox bios folder and in the external datastorage bios folder.
When I use only the SD card with Recalbox, the PSX works perfectly fine and the games too. No issue at this point.
When I connect to the external Data storage, the system tells me the bios are missing but when I check, the Bios are present in both : \RECALBOX\share\bios & \ASGARD-RETRO\share\bios (ASGARD-RETRO is the name of my External DataStorage)

I wanted to know if someone had a solution or knows of the issue please?
Thanks everyone,
Guts
PS : I didn't find another post with this issue but if someone already asked please excuse me for asking again

EDIT : The solution has been found :

Ok I found the solution I post it here if anyone needs it in the future :
It's all my bad the Names where not in lowercase, and even if the uppercase does work without external datastorage it doesn't when using an USB Storage.

@GutsNaem
Ok I found the solution I post it here if anyone needs it in the future :
It's all my bad the Names where not in lowercase, and even if the uppercase does work without external datastorage it doesn't when using an USB Storage.

Hello everyone and sorry to bother you.
Before taling about the problem I precise that I followed the guide to use external datastorage for Roms and that I put BIOS files both in the recalbox bios folder and in the external datastorage bios folder.
When I use only the SD card with Recalbox, the PSX works perfectly fine and the games too. No issue at this point.
When I connect to the external Data storage, the system tells me the bios are missing but when I check, the Bios are present in both : \RECALBOX\share\bios & \ASGARD-RETRO\share\bios (ASGARD-RETRO is the name of my External DataStorage)

I wanted to know if someone had a solution or knows of the issue please?
Thanks everyone,
Guts
PS : I didn't find another post with this issue but if someone already asked please excuse me for asking again

EDIT : The solution has been found :

Ok I found the solution I post it here if anyone needs it in the future :
It's all my bad the Names where not in lowercase, and even if the uppercase does work without external datastorage it doesn't when using an USB Storage.