Microsoft has denied it provided the US intelligence services direct access to its products for interception efforts.
In a statement it said it has clear principles to guide the response for government demands for customer information for both law enforcement and national security issues.
It said that it provided customer data only in response to legal processes and its compliance team examines demands closely, rejecting those it demmed invalid.
Microsoft also said it complied only with orders about specific accounts or identifiers, not blanket orders.
“To be clear, Microsoft does not provide any government with blanket or direct access to SkyDrive, Outlook.com, Skype or any Microsoft product,” it said.
When a product was updated, legal obligations could require it maintain the ability to provide information in response to a law enforcement or national security requests.
Files provided to the Guardian by NSA whistleblower Edward Snowden claimed to show that Microsoft helped the NSA circumvent its encryption to address concerns that the agency would be unable to intercept web chats on the new Outlook.com portal.
It also claimed the agency already had pre-encryption stage access to email on Outlook.com, including Hotmail; and Microsoft worked with the FBI to allow the NSA to have easier access via PRISM to its cloud storage service SkyDrive, which now has more than 250 million users worldwide.