Northrop Grumman argued in court and legal filings that it had no intention of cutting off email services, but demanded to be paid for past and future services.

“We are willing to commit to continuing the service to April 30, 2018, but we can’t do it for free,” Northrop Grumman lawyer Brett Ingerman said.

Ingerman argued that VITA, not Northrop Grumman, was to blame for the showdown by failing to provide a clear plan for disentangling the state from a 13-year contract that has paid the company $2.4 billion.

“It is the commonwealth that is putting its own messaging system at risk,” he said.

But the state’s lawyers, from the McLean-based firm Hogan Lovells, said Northrop Grumman itself had made clear that it would take the steps necessary to begin transitioning the service to Tempus Nova only if it were paid additional money for tasks it contends are beyond the scope of the contract.

“This dispute is all about money,” Connolly said.

VITA contended that it is paying $900,000 a month for Northrop Grumman to provide a Microsoft-based email service the state doesn’t want, while a cheaper, Google-based provider has been under contract for 14 months and paid for services it has been unable to provide.