The non-exclusive deal is worth $300 million, which both companies will spend on collaborative efforts, testing, deployment and joint sales and marketing. HP and Microsoft said they have about 20,000 joint customers.
The vendors said they plan to pool their IT services efforts in such areas as messaging and unified communications to deliver voicemail, email, video conferencing and other communications under a single console.
Hewlett-Packard said it will focus on collaboration and content management, pointing out that the company has a large installed customer base that uses Microsoft's Exchange Server.
Ann Livermore, executive vice president of HP's Technology Solutions Group, said IT shops are also interested in business intelligence and business process integration services, as well as products and services necessary to make Microsoft technology reliable, scalable and secure.
Earlier this year, Microsoft cut a four-year deal with Nortel to bring unified messaging to the enterprise. There was no dollar amount made public for that deal.