JSI Tip 9496. You cannot save or copy files from a Mac OS 9.x computer after you install security update 885250 (MS05-011)?

Microsoft Knowledge Base Article 896433 contains the following description:

After you apply the MS05-011 security bulletin, you cannot save or copy files from a Mac OS 9.x computer. Mac OS 9.x computers use AppleShare IP 6.3 technology.