The company advises users to upgrade to paid commercial subscriptions before the deadline for account deletion Windows Azure, Microsoft’s public cloud computing platform, became generally available in 21 countries on Monday, Microsoft bloggers said. SQL Azure, offering cloud-based relational database capabilities, also became available.Windows Azure features compute, storage, hosting, and management capabilities. Microsoft first revealed Azure in October 2008. The platform has been available in a Community Technology Preview phase. As of 12 a.m. Greenwich Mean Time on Feb. 2, Microsoft begins charging for Azure, the Azure Team blog said.[ InfoWorld’s Paul Krill got the scoop last week that the Sun Cloud service planned by Sun Microsystems will not see the light of day. ] “Since January 2010, thousands of customers have moved from CTP to production and partners like Origin Digital, GXS, tradefacilitate and 3M are actively building and deploying solutions to the Windows Azure platform. Starting today, they, along with all of our partners, will be able to begin selling their solutions to their customers, ultimately enabling them to reach new markets and increase their revenue,” the Azure blog said.Customers who have not yet upgraded Windows Azure CTP accounts to paid commercial subscriptions will have service disabled and their data on Windows Azure Storage will be made read-only. SQL Azure CTP customers who have not yet upgraded can keep using existing databases but cannot create new ones. On March 1, SQL Azure CTP accounts that have not been upgraded will be deleted. Windows Azure Storage CTP accounts that have not been upgraded will be deleted on April 1.This story, “Microsoft Windows Azure cloud reaches general availability stage,” was originally published at InfoWorld.com. Follow the latest developments in cloud computing at InfoWorld.com. Cloud Computing