Hi Faltaman,
The profile you're trying to remove is stored in the Windows Registry.
If you are familiar with regedit, these instructions should help you. If not, please reply with a request for more details.
I've copied and pasted the instructions from this link below:
Superuser.com - networking - Remove a known network from Windows 8 - Super User
Find and delete the registry keys for the unwanted networks under these locations:
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows NT\CurrentVersion\NetworkList\Nla\Cache\Intranet
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows NT\CurrentVersion\NetworkList\Profiles
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows NT\CurrentVersion\NetworkList\Signatures\Unmanaged Note:
The known networks described above are separate from wireless user profiles, which store SSIDs, WPA2 passwords, etc. The UI for managing wireless user profiles is also gone. These can be wiped clean by removing the wireless adapter from Device Manager (Windows will restore it fresh) or removed individually with
netsh wlan delete profile "profile name"