When applying the 051112 update, the base/root .htaccess file must first be corrected or you will probably get an internal server error for your entire site:
Change This:
// BOF: MS2 update 501112-Added
# If Search Engine Friendly URLs do not work, try enabling the
# following Apache configuration parameter
#
# AcceptPathInfo On
// EOF: MS2 update 501112-Added
to this (adding in the correct comment symbol first and last line):
# // BOF: MS2 update 501112-Added
# If Search Engine Friendly URLs do not work, try enabling the
# following Apache configuration parameter
#
# AcceptPathInfo On
# // EOF: MS2 update 501112-Added
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