Half of Fortune 500s, US Govt. Still Infected with Trojan

What exactly is taking these guys so long to fix their systems? It's not like they don't have the time, money and/or resources. roll eyes (sarcastic)
More than two months after authorities shut down a massive Internet traffic hijacking scheme, the malicious software that powered the criminal network is still running on computers at half of the Fortune 500 companies, and on PCs at nearly 50 percent of all federal government agencies, new research shows.