We hereby notify of trouble caused by our virus pattern file as reported by the press.

1. Outline of the problem

We confirmed that a virus pattern file which we distributed on April 23, 2005, from 7:33 a.m. to 9:02 a.m., Tokyo Local Time significantly slowed the performance of our customers’ computers and in some cases made their computers inaccessible immediately after they updated with the file. This trouble was caused by insufficient work in compatibility testing of the product with the operating system before it was released.

In order to minimize the effect of the trouble, we started to release a replacement virus pattern file on 10:51 a.m. of the same day, opened a 24-hour customer support center and established a temporary facsimile box and an email contact to respond to inquiries from our customers.

We promise that we will further strive for and improve our quality control to avoid future occurrences of similar problems.

2. Effects on our business performance

We are currently estimating the effect of the trouble on our consolidated business results for the second quarter of the fiscal year ending December 2005 as well as to our business forecast.

About Trend Micro:

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