Microsoft has come under fire from Cert, the US Computer Emergency Response Team, which since 26 May has published 111 security alerts and bulletins relating to Microsoft Internet Explorer.
Many of these problems will be fixed with the service pack, which is due out later this summer. However, the higher level of security in Windows XP SP2 will mean certain functions on websites may no longer work.
Stuart Okin, chief security officer at Microsoft, urged organisations to consider the impact of SP2 when designing websites. "Balance between the richness of the website and understanding security," he said.
Among the biggest problems could be the pop-up blocker. This is designed to prevent pop-up advertisements being downloaded onto an XP user's desktop. However, Okin noted that some sites use pop-ups to allow users to enter information such as log-in details.
XP users who access sites using such features will be unable to see the pop-up after they install SP2.
Another potential problem concerns printing. In a technical document on SP2 software compatibility, Microsoft said, "With SP2, you cannot print or print preview a web page that includes an ActiveX object." The printing function is blocked. The only way for an end-user to print the page is to turn off a Windows registry setting called "local machine zone lockdown". Microsoft advises against this, as it lowers security.
In a corporate IT environment, Microsoft warned that the Windows Firewall, which is switched on by default, will interfere with the operations of several Microsoft System Management Server functions. It suggested a three-step process to fix this problem, which involves configuring each desktop machine manually.
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