ISAPI_Rewrite on IIS

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I know a while back someone was looking for a mod_rewrite for IIS. I had
mentioned that ISAPI_Rewrite is supposed to work quite similar.

Well, I finally had to use it. Here are a few notes for those who may
need to use it (free version is what I used):

* The entire request is used for pattern matching (including query string).

* you must use the global httpd.ini file to store your rules

* RewriteCond %HTTP_HOST www\.example\.com in IRW is equiv to
mod_rewrite's RewriteCond % www\.example\.com

* negative lookaheads must be used [ (?!.*DONT_FIND).* ] for negative
matching in RewriteCond in IRW where in mod_rewrite you could simply
negate it be prepending the pattern with !

* apache's QSA flag is not supported, instead, you need to use an
additional rule to check and capture the query string to append it to
the rewrite

* because you are using the global config file (stored in the IRW
install directory), you must apply a RewriteCond to all RewriteRules or
it will effect all sites on the server.

* apache's [NC] flag is the same as IRW's [I] flag

* [L] flag between both are the same

* [PR] in IWR is equiv to apache's [R=301]

* [F] in IWR is equiv to apache's [R=403]

* apache can check if files/directories exist, IWR cannot. For one
work-around on this, see my post at:

Hope this helps somebody...

Justin Koivisto, ZCE -

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