How can a client control the access of an administer? My computer is being controlled by someone unknown and with bad intent. They reconnect using Bluetooth DUN to my USB Hub via an RF and I need to learn how to stop access. Please help!

This is usually because that remote access has been granted due to something that was installed — a compromised application that was acquired somewhere (some antivirus and anti-malware tools have themselves been vulnerable), some cracked software, from torrented applications, sometimes by weak passwords or exposed passwords or re-used passwords, sometimes via a compromised router or other device on the local network.

Usual remediation for these cases: back up all of your data to external storage, wipe the disk, reinstall OS X and apps from known-good sources, change all your passwords to more secure passwords or to Keychain automatically-generated passwords. Then watch your bank and credit cards for fraud.