SEATTLE (Bloomberg) — Microsoft Corp., the world's largest software maker, plans to let small-business customers purchase advertising linked to search results on IAC/InterActiveCorp.'s Ask.com site.The ad sales will be handled by AdManager, one of Microsoft's Office Live services, the Redmond, Washington-based company said yesterday in an e-mailed statement. AdManager already lets customers purchase ads on Microsoft's own search engine.

Microsoft is counting on the Office Live programmes, which handle online tasks such as managing customer records and viewing company data, to attract more small-business customers. The Ask.com announcement steps up competition with Salesforce.com Inc., which offers similar programmes and lets clients purchase ads with Google Inc., the top internet search engine.

Ask.com is the fourth-largest search site, measured by the percentage of internet queries it handled in June, according to research firm ComScore Inc. It trails Google, Yahoo! Inc. and Microsoft.