Invalid STFS Package

Hello! I’m new to the community, and could use some help. I’m trying to create a modded save for a friend on Borderlands 2, using both Horizon and Gibbed BL2 save editor. I’ve got the .sav created and everything, but when trying to inject the created file (Made in Gibbed), I get the Invalid STFS Package error. When trying to open a fresh save in Gibbed, I get the message, “Failed to load save: Cannot load XBOX 360 CON files, extract saves using Modio or equivalent”. Anybody know how to fix this? Help would be greatly appreciated!

Just replace the .sav file with the modded one.

i get the same STFS error but for opening it remember to change the thing on right next to the save file to xbox360