'After installing my license file for 8PI Control Panel, I cannot see it from the 8PI Control Panel installation directory with Windows Explorer.

Though, 8PI Control Panel does not complaint about licensing - so, I suspect that it can find it anyway. Where is it?'

This issue happens with Windows 7, due to UAC (User Account Control) features.

According to the rights that you have as a user, Windows OS may prevent you from copying data into the c:\Program File directory or one of its subdirectories.
Instead, Windows copies it into what is called the 'Virtual Store', located here: C:\Users\<your user account>\AppData\Local\VirtualStore . 

It can be troublesome because even though you finally succeed in manually copying a file into the 'Program File' directory, the system will keep on using the one located into the Virtual Store.

This might prove problematic when you try to append a license file from Byte Paradigm with the license of a newly purchased device.

For now, you'll need to properly edit the file located into the Virtual Store.