When another browser is installed, sometimes when a security package interferes with it, etc. Your post is a little light on details but with each patch there is a KBnnnnnn that you can research and install manually if it fails and you really want that patch.
I don't how long this has been the situation on my system,i just noticed that my Laptop "was downloading" security updates but my desktop "was not". On going to, "Microsoft Windows Update",i got the message, "Thank you for your interest in obtaining updates from our site". This website is designed to work with Microsoft Windows operating systems only. To find updates for Microsoft products that are designed for Macintosh operating systems,please visit http://www.microsoft.com/mac/.
I don't have anything to do with Macintosh on my system, i personally,purchased and installed Windows XP (Genuine Copy) Validated by Microsoft Advantage Tool,so can anyone tell me why i cannot install Security Updates and any other Updates.