In 1982, Kevin Flynn, a former ENCOM programmer with Group 7 access tried to hack into ENCOM's mainframe in order to find incriminating evidence on Ed Dillinger. However, he was kicked out of the system and as a result many group 7 programmers who were working on projects were restricted access from the system as part of the MCP's security lockdown. This included Alan Bradley, who at the time was working on his program, Tron. The ban was temporary however, as Tron escaped the game grid and destroyed the MCP, thus destroying the restriction.
During the existence of the Flynn Lives Organization (in both the TRON universe and our real world), the unknown individual "ZackAttack" manufactured ENCOM Badges, which supposedly granted Group 7 Access to holders.