The German teenager allegedly behind the havoc-wreaking Sasser virus has gone on trial in Germany.
Sven Jaschan has been charged with sabotaging computers, disrupting public services and altering data illegally.
The 19-year-old is being tried in a juvenile court as he was 17 when he allegedly spread the Sasser worm.
The damaging worm targeted Windows-based computers in May last year and caused widespread disruption. This was despite Microsoft having issued a patch against the Windows vulnerability the worm took advantage of the previous month.
Organisations and firms that had failed to fully patch their systems against Sasser included British Airways, which was forced to delay flights after its check-in systems crashed; and the Maritime and Coastguard Agency, where staff were forced to return to manual map reading after their computer systems failed.
Microsoft offered a $250,000 (£135,000) bounty to find the people behind Sasser, and this produced a tip-off that led to Jaschan’s arrest.
Jaschan’s trial is expected to last three days. He now works for German security software company Securepoint.