yesterday, and no trading took place.

According to Greg Wojciechowski, the chief operating officer of the BSX, the computers failed while technicians were upgrading the system.

It is the first time that BSX has been unable to operate since a new system was installed last December.

Mr. Wojciechowski said: "Due to a technical problem during a trading system application upgrade of the BSX's BEST trading system it was unable to operate on November 9, 1999.

"The system will be fully restored for the opening of trading on November 10, 1999. We apologise for the inconvenience and note that there has been only one other time since December 1, 1998 that there has been an interruption in service, so on balance the platform has performed well.

"We will do everything in our power to make sure this does not happen again.'' On Monday the BSX traded on a volume of 6,741 shares valued at $117,333.40.