Microsoft Product Support Center

http://support.microsoft.com/default.aspx?scid=fh;RID;faqs
Find product updates, service packs, hot fixes for all Windows products. Check out the "Get Most Recent Version" topic category.

Novell Product Updates

http://support.novell.com/filefinder/
Find product updates, patches and Technical Information Documents (TIDs) by product name.

Apache web Server

http://httpd.apache.org/
Documentation, support, security info and patches for all versions of Apache.

HP's IT Resource Center

http://us-support.external.hp.com
Find support information by product, patches, knowledge base, use the HP software update manager. Requires you to register to use these services.

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