SEATTLE – Microsoft rolled out on Thursday its MSN Postmaster Web site, which offers tools and services aimed at combating spam ? unsolicited commercial emails.

MSN Postmaster marks the software giant’s latest effort to increase its presence in the security arena, a lucrative area that has attracted a large swath of competitors, CNET.Com reported.

An online resource, Postmaster offers tools to help Internet service providers, e-mail service providers and legitimate bulk e-mailers combat junk e-mail, streamline the reporting process for spam and assist in delivering legitimate bulk e-mail to MSN Hotmail users.

Postmaster will also include the software giant’s new Smart Network Data Services, which will provide reports on the types of e-mail being sent to MSN Hotmail accounts. The tracking service will inform ISPs of the volume of e-mail being sent from their IP address to MSN Hotmail users and the percentage of that e-mail that has been tagged as spam by either Hotmail filters or the user themselves.

With that information, ISPs can identify and clean compromised PCs and question bulk e-mailers to determine whether they are spammers.

Security experts say ISPs are reluctant to shut down customers’ accounts, even if they appear to be inadvertently pumping out spam. For ISPs, it means lost revenue when they shut down a customer’s account while trying determine whether or not the e-mail their customer is distributing is legitimate.