So I recently had to wipe my whole computer of all its data. and my team is using unreal 5.1.0 for development which can no longer be installed via normal methods but I still have the version folder on an external hard drive. Is there any way I can make epic install this version or am i just out of luck?
You would suggest that you try to remove all files including the Epic Launcher, then proceed to install Unreal Engine again.
You need to provide more information however, how and why can’t you install it? What errors appear, etc?