Record company Sony BMG, yielding to consumer concern, said on Wednesday it was recalling music CDs containing copy-protection software that acts like virus software and hides deep inside a computer.

"We share the concerns of consumers regarding discs with XCP content-protected software, and, for this reason, we are instituting a consumer exchange programme and removing all unsold CDs with this software from retail outlets," Sony BMG said in an statement.

The XCP software used by Sony BMG, which was developed by British software developers First4Internet, leaves the back door open for malicious online hackers.

Sony BMG, in a separate statement, also announced it would distribute a program to remove the software from a PC where it jeopardizes security.

"We deeply regret any inconvenience this may cause our customers. Details of this [recall] program will be announced shortly," Sony BMG said.

The withdrawal is set to affect millions of compact discs from artists such as Celine Dion and Sarah McLachlan, but Sony did not give exact figures or the names of the artists affected.

Sony reiterated that the copy-protection software only installs itself on personal computers and not on ordinary CD and DVD players.

Microsoft Corp.'s (MSFT) anti-virus team said on Tuesday it would add a detection and removal mechanism to rid a personal computer of the Sony's DRM copy-protection software. The software installs itself only on PCs running Microsoft's Windows operating system.

The flaws of the copy-protection software became acute last week, when the first computer viruses emerged that took advantage of the security holes left by the program.

Responding to public outcry over the software, the music publishing venture of Japanese electronics conglomerate Sony Corp. (SNE) and Germany's Bertelsmann AG had said on Friday it would temporarily suspend the manufacture of music CDs containing XCP technology.

It then provided a patch to make the hidden program more visible. At the time it did not recall the CDs or offer a program to remove it from computers. The initial measures still left PCs vulnerable, according to software engineers.

The program will have installed itself on a Windows-operated personal computer when consumers wanted to play certain Sony BMG music CDs. The program forces consumers to use a music player that comes with the program.

Sony BMG has positioned itself as a defender of artists' rights. It re-emphasized on Friday that copy-protection software is "an important tool to protect our intellectual property rights and those of our artists."

Sony BMG last week was targeted in a class-action lawsuit complaining that it had not disclosed the true nature of its copy-protection software.