One complex situation when a computer or laptop infected by two different backdoor and Trojan was solved as follow:
UltraDefragerFraud was detected.
UltraDefragerFraud is a virus/malware which pop ups fake alerts much similar to windows warnings that try to trick the infected person to buy a product. Ultra Defragger Virus/Malware is an example to software that uses this malware that way.
Cleaning programs such this, can frustrating, but when digging into in on internet the solution will be found. The most important thing here is to work safety on a flash drive or CD and immediately disconnect the computer from internet.
In most cases, using the Symantec Endpoint Recovery Tool (SERT) will be perfect as it start the computer ,connects to the internet (in new edition) and pull the latest virus and malware definition update. Then it scans the computer and removes viruses and malwares it found.
For   UltraDefragerFraud malware the Symantec Endpoint Recovery Tool didn’t recognize the malware and Symantec was aware of this to deploy the Norton Power Eraser tool (NPE).

1.Download the Norton Power Eraser tool(NPE)
2.restart it in Safe Mode
3.kill any processes associated with UltraDefragerFraud infections
4.Run the Norton Power Eraser while follow the instructions.

Many Thanks to Shimey Bejerano for the update.