Trojan-PWS.Tanspy is a malicious Trojan application that is designed to get secretly into your computer and open a conduit for infecting your machine with different spyware. Usually Trojan-PWS.Tanspy comes bundled with other parasites or via browser security holes. Once it is installed, Trojan-PWS.Tanspy will download additional adware and spyware onto your system. Trojan-PWS.Tanspy also monitors and records your keystrokes and scans your computer for stored passwords. Trojan-PWS.Tanspy is a very dangerous threat to the security of your personal and financial data and should be removed without delay.

Source: http://www.spywareremove.com/removeTrojanPWSTanspy.html