You may have encounter problems from users that a virus occurs on the computer when they connect their removable devices such as USB stick or external hard drives to the computer. This is due to inappropriate files being stored in the the drives and accessed on the computer, which causes the virus to spread across the network and cause disruption to the entire site. You can prevent this from happening by disabling removable devices from connecting to the computers by following the steps below (This issue applies to Windows Server 2008 R2, Windows Server 2012, R2):
1) Logging in to DC server
2) Launch Group Policy Management from Start -> Administrative Templates
4) Launch All removable Storage Classess Deny all Access policy
5) Click on Enable radio button
6) Press Ok and close group policy editor and group policy management
7) Launch command prompt from start/All Programs/Accessories
8) From the command prompt type the following command gpupdate /force
9) If gpupdate requires you to reboot the computer, press n for no and press n again if it is asking you to log off from the server
10) Reboot the client machine and if you try to insert a USB pen or external hard drive, the computer will not detect it and will not be able to access the drives
You can also apply the same settings for user bases by following the same path under user configuration. Instead of rebooting the client computer, you can log off from the computer and log in again.
After you have performed the steps the users should not be able to connect their removable storage device to the computers and prevent virus from spreading across the network.