I've noticed a marked increase in virus activity over the last week. The main virus is a variation of Virus.Win32.Rbot.gen. When a system is infected, it will make changes to the root of any drive letter it sees. All of the folders are marked as system and hidden so that the user with standard Windows settings will no longer see them. It then replicates itself, taking on the names of the folders it just hid and giving itself an icon that looks like a folder icon. The unsuspecting user will click on the virus thinking that he is opening his own folders. This is how it spreads from one workstation to another across a network. The network server directories are hidden and replaced with virus executables. Other users then open the virus looking for their folders. The virus will also drop copies of itself as porn.exe, sexy.exe. and x.mpeg.
Many of the major antivirus products will not detect this virus. I have found that Kaspersky does a fair job at detecting and getting rid of most of the virus. You may still have to delete some files by hand. PandaSoftware activescan will detect the virus,but you must delete it by hand. If you are not an expert at killing processes and editing the registry, it would be best to call a professional if your system is infected with this virus.