BOULDER, Colo. -- The University of Colorado at Boulder said Thursday that a security breach announced last week was actually not a breach.

A "forensic analysis of a computer suspected to have been compromised last week revealed no malicious software, and no exposure of student and staff private data," CU said in a news release.

The director of IT security said the problem was caused by an interaction between two incompatible software programs that mimicked behavior consistent with a malicious file.

Because the university believed that malicious software was installed, the school notified the 9,000 students and 500 staff of the threat. The computer affected contained the names, Social Security numbers, addresses and grades of all students and instructors in the Continuing Education and Professional Studies division.

"While the data was not compromised, this incident still reinforces the need to continue to constantly improve IT security at CU. We also intend to share our discovery of the software incompatibilities with our colleagues," said Dennis Maloney, chief technology officer for CU-Boulder.

Chancellor G.P. "Bud" Peterson reiterated, "While I am relieved no personal data was exposed in this incident, it reinforces our need to continue to emphasize to our faculty and staff the measures we all must take to protect important data."

Because of the security concern, CU announced several changes.

The university's IT Security Office will work with Continuing Education to improve security through increased awareness and training, and will re-scan systems for private data and remove any if found. The private data on the laptop has been removed.

The university will aggressively continue the campaign to eliminate Social Security and credit card numbers from all systems across the campus.

The university will expand its program to encrypt laptop computers across campus.

The campus will implement improved password management procedures during fall 2008.

The campus will complete security training for all faculty and staff by June 30, 2008.