Writing in his bog, Avast COO Ondrej Vlcek said that abandoning Windows XP was a big mistake, particularly as Microsoft has been rubbish at getting people to upgrade.
He said that security products can only do so much to keep Windows XP users safe once Microsoft stops patching the operating system's future vulnerabilities.
Abandoning XP will not only affect Windows XP users, but will create a big security problem for the whole ecosystem, says Vlcek.
"Tens of millions of PCs running XP connected to the Internet, unpatched and without security updates, are just waiting to be exploited. The vulnerable OS will be an easy target for hackers and be seen as a gateway to infect other non-XP operating systems," Vlcek said.
Plenty of essential devices, like ATMs, are running Windows XP, and will be left exposed, he warned.
However to be fair to Microsoft, it has given its users a jolly long time to quit their XP addiction. We would have thought that there would be a market for a security product which stays ahead of the hackers – if only Vlcek knew of an AV company which could do that.