Symantec leveraged Thuridion's extensive Windows development expertise, first in the development of key components for Norton Desktop, then in the development of Norton Anti Virus for Windows. Thuridion developed Norton Anti-Virus for Exchange, and has been a core contributor to over 10 versions of Symantec Anti Virus products. Thuridion also joined Symantec during heavy acquisition periods to port products and integrate them into the Tivoi, OS/2, Lotus Notes, and HP Openview environments . Thuridion has managed and provided resources to Symantec for up to seven overlapping projects at any one time.