You may have a flash drive infection. These worms travel through your portable drives. If they have been connected to other machines, they may now be infected.
Please download Flash_Disinfector.exe by sUBs from http://download.bleepingcomputer.com/sUBs/...Disinfector.exe
and save it to your desktop.
Double-click Flash_Disinfector.exe to run it and follow any prompts that may appear.
Note: Some security programs will flag Flash_Disinfector as being some sort of malware, you can safely ignore these warnings
The utility may ask you to insert your flash drive and/or other removable drives including your mobile phone. Please do so and allow the utility to clean up those drives as well.
Wait until it has finished scanning and then exit the program.
Reboot your computer when done.
Note: Flash_Disinfector will create a hidden folder named autorun.inf in each partition and every USB drive plugged in when you ran it. Don't delete this folder. It will help protect your drives from future infection.
Now, download Malwarebytes from http://malwarebytes.org/
update it and run a full scan. Remove any infections found and post the results in your next reply.