Quoting from the SWsoft official announcement:

SWsoft, Inc. has signed an agreement with Microsoft Corp. that helps SWsoft enhance its customers' experience. The agreement is for a three-year period and benefits SWsoft enterprise and hosting customers running Virtuozzo for Windows Server virtualization software.

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As part of the agreement, SWsoft will receive 24-hour, 7-day support from Microsoft for its enterprise and hosting customers operating Windows-based applications within Virtuozzo virtual environments...