A main computer failure at the Sonoma County courthouse shut down telephones and access to electronic case management systems for about five hours Thursday.

The crash happened at about 9:45 a.m. and was repaired by 3:05 p.m., said Jose Guillen, the court's executive officer.

It was caused by broken cooling fans in the central server that runs all computers used by court clerks, judges and other administrative employees.

County offices, such as the district attorney and public defender, were not affected.

During the outage, courtroom minutes were entered by hand and all telephone communication was cut off. The automated juror summons system also went down, Guillen said.

New equipment was trucked in and installed by a San Jose vendor.

No trials were postponed by the crash but the lack of current information may require some bail refunds in traffic court, Guillen said.

Guillen said the state-run courts will consider stocking spare parts in the future. A complete backup system would cost $280,000, Guillen said.