An update to CA Antivirus has turned out to be quarantining some of Windows XP’s core files, leaving XP users who happen to keep their antivirus up to date out in cold.

Haven't seen one of these in years

Naturally the source of the problem has since been tracked down and amended, but the backlash has been furious, as you might expect. The issue seems to have arisen from a combination of the manner in which CA detects and quarantines possible infections.

The Register is reporting that the whole affair stems from an issue with the detection of “Win32/Amalum” with extensions including ZZNRA, ZZOFK and ZZNPB being automatically appended an AVB extension and quarantined. The only problem is that this seems to have included a number of fairly important Windows’ system files.

What’s most disconcerting about the whole affair is that CA’s antivirus seems to have included a setting that allows for the automatic deletion of quarantined files, a situation that has users crawling the walls in a combination of fear and frustration in CA’s forums. Moreover, the response hasn’t been an entirely confidence raising one, with forum users advised, “For now though, you will just have to managewithout[sic] an anti-virus till CA can fix it. Not good enough but at least you will still be able to use your pc.”

You have to wonder sometimes how these things make it through testing… You can read more about it at The Register, here.