Following the dissolution of the Soviet Union, Pajitnov faced the challenges of navigating the newly formed Russian economy and legal system, particularly concerning the Tetris rights.

Pajitnov moved to the United States and joined Microsoft. This marked a significant shift in his career, allowing him to work on various puzzle games and contribute to Microsoft's entertainment software offerings.

During his time at Microsoft, Pajitnov worked on various projects, including the puzzle game "Pandora's Box" and designing puzzles for "Microsoft Puzzle Collection" and "Microsoft Entertainment Pack: The Puzzle Collection".