Microsoft CEO Steve Ballmer met personally with U.S. Department of Interior officials -- and apparently made quite an impression -- before the agency decided to exclude Google and other rivals by only accepting bids involving Microsoft technologies to upgrade the email system for the department's 88,000 employees.

It was "a fantastic show of support from the highest level of leadership at Microsoft," one Interior Department official wrote afterward, according to newly unsealed court documents.

The Feb. 4, 2010, meeting doesn't appear to have been the deciding factor in the agency's decision to go exclusively with Microsoft's online email and collaboration services, and federal judge Susan Braden writes that she sees nothing improper in Microsoft's display of "competitive zeal and interest in customer satisfaction."

Nonetheless, Braden has issued a preliminary injunction that prevents the agency from going forward with the Microsoft-based contract so that it can reconsider whether bidders offering Google Apps or other technologies should also be allowed to submit proposals.

It's an important victory for Google in its effort to loosen Microsoft's grip on a key government contract. The ruling could help set the tone for bidding on future federal tech business.

The case also illustrates Google's struggle to be considered as a serious alternative for such technologies. Court documents (PDF, 27 pages) detail the behind-the-scenes discussions that led to the agency's decision -- painting Microsoft as the incumbent insider and Google the upstart outsider.

The exchanges surrounding Ballmer's meeting with agency's officials exemplify the situation.

The meeting "was a great opportunity for [Deputy Secretary] David [Hayes] to hear what we are working on together and a fantastic show of support from the highest level of leadership at Microsoft," wrote Deputy Assistant Secretary Jackson in a note afterward to Microsoft Teresa Carlson.

"Thank you for taking the time to meet with me," wrote Ballmer in a follow-up message to Hayes. "I share your passion around the growing partnership between Microsoft and the Department of the Interior. You have my personal commitment to success on this Exchange Online Project. I agree with you that this effort—as a first in Federal—should be celebrated appropriately."

Despite the collaborative tone, Jackson assured Google VP Michael Lock in an email message in June that the agency had "not finalized its procurement strategy for the planned cloud messaging solution. We continue to evaluate all options in light of our business requirements."

A big part of Google's challenge was skepticism inside the federal department about the ability of Google Apps to meet security standards. It wasn't until last July that Google announced a government-only version of Google Apps meeting the requirements of the Federal Information Security Management Act.

[Update, 2 p.m.: To clarify, Google was actually the first (and so far the only) company to receive FISMA certification for its cloud messaging and collaboration services. As of last month, Microsoft said its Business Productivity Online Services offering -- the specific technology at issue in the proposed Interior Department contract -- was still awaiting FISMA certification.]

Microsoft today issued this statement on the court ruling.

“The Department of Interior determined that the dedicated, U.S.-based cloud solution offered by Microsoft met its minimum security and other requirements after a careful and thorough evaluation, and that Google’s solution did not. The judge’s decision does not address this fundamental determination. We believe the full record will demonstrate that this award is in the best interest of the government and taxpayers.”

The ruling cites an incomplete administrative record as one of the reasons for issuing a preliminary injunction in the case. The judge writes that she "finds it unusual that the Deputy Assistant Secretary Jackson had 'regular monthly one-on-one' meetings with (Microsoft exec) Ms. Carlson, but apparently took no notes or didn’t maintain them."