The Web hosting service McColo was shut down earlier this month, as it has been proven beyond reasonable doubt that the company was indeed responsible for about three quarters of the worldwide Internet spam. Two of their ISPs ended their collaboration with McColo after they were provided undeniable proof that McColo had connections with botnets and cyber-crooks.

According to Symantec and their MessageLabs, it seems that McColo was the host of a whooping 80% of the spam that filled your inbox. Since McColo was closed down, the Internet has enjoyed a full two weeks of better traffic, with less spam. After these two weeks were up, it appears that spammers have managed to find new Internet Service Providers and also bandwidth providers. The spammers needed new ISPs after McColo got disconnected from Hurricane Electric.

Srizbi, which is a botnet responsible for about half of the world’s spam, has recently been revived and Symantec officials said that spam resurgence is already at 37% and signs show that the resurgence will continue to rise. Another two botnets have been also recently revived, namely Asprox and Rustock. Botnet Cutwail wasn’t part of McColo, so it was never shut down, yet Mega-D is also rising.

The company Marshal predicted that there will be a spike regarding fresh spam, until the spammers will reconnect with the infected computers. Spam will be expected to climb back to its initial rates. Even though the shutting down of McColo was a breakthrough in the fight against spam, small businesses that don’t have a strong or sufficiently well-funded IT department are the easiest targets for marlware, spyware, spamming and viruses.