Microsoft has published a list of applications that will need extra configuration after its Windows XP Service Pack Two (SP2) is installed.
Nearly 50 applications will need fixes, primarily due to the new firewall which blocks specific ports.
Some of Microsoft's own software is also showing problems with the new code.
A full list of known applications that will need work is on the Microsoft Knowledge Base website here.
"In virtually all cases this just needs manual port allocation," said Paul Randle, product marketing manager for SP2.
"In some cases it is also affecting older versions of software that are not a top priority for software vendors to test. We will keep the list up to date in the future."
A number of major vendors are on the list, including Symantec. The security firm said that consumers who run Norton AntiVirus, Norton Personal Firewall, Norton SystemWorks and Norton Internet Security will need to install the product update in order for Microsoft's Windows Security Center to accurately display the status of their security protection.
"Enterprise customers using Symantec Client Security and Symantec AntiVirus Corporate and Enterprise Edition will also need to install the update if their computer is not a member in a Windows domain," said Symantec.
The currently available updates are needed because Symantec includes anti-tampering security in its software so that hackers cannot easily change settings.
Microsoft has also identified over 100 other software vendors which may find that applications "work differently" with SP2.
These include applications and games from Adobe, McAfee, Lucas Arts and Computer Associates.
Details can be found on Microsoft Knowledge Base website here.
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