Hi all, Could anybody point me in the right direction re a regular expression I try to implement as a <FilesMatch> directive in Apache 2.4 please? I would like to deny access to any files in a specific directory which file extension is not "whitelisted". The rule should be case insensitive. <Directory ... > <FilesMatch [WHITELIST] > Require all denied </FilesMatch> </Directory> I tried the following as [WHITELIST], but to no avail: "(?<!\.png|\.gif|\.jp?g)$" -> works, but is case insensitive "(?i:<!\.(png|gif|jp?g))$" -> does not match anything !"(?i:\.(png|gif|jp?g))$" -> does not match anything "(?i:<!\.png|\.gif|\.jp?g)$" -> does exactly the opposite (not negated) ...plus 100 combination, which all result in parsing errors :-) My understanding is, that ?i: means case insensitive and <! negates the expression. Any idea what am I doing wrong or how to achieve what I outlined above? Many thanks Michael