Where did Angela get the virus that was in the red disc?

At the beginning of the movie, she was talking to someone about debugging their software (3-D game, Wolfenstein-like) because a virus had gotten into it. She mentioned that she could clean it up and said a friend of hers collects viruses (virii?). The FedEx guy came, with a package from Dale at Cathedral which contained the Praetorian bug (the pi sign) and when she signed for it, she said she had something going out. She had copied the virus from the first conversation onto a disk and sent it to Dale. Then later, when she was at Cathedral after having gotten Ruth Marx out of the building, she found the disk in a drawer while looking for a blank disk to copy the proof of the criminal activity. Blue disk=copy of proof, red disk=virus.

At the convention, she popped the blue disk into the computer and emailed the proof to the FBI. After that sent, she took the blue disk out and put the red disk in, and Jack Devlin pushed her aside and pressed the Escape key, which set the virus in motion.