Just installed Processwire on shared hosting using IIS on windows. Only problem I had was with the .htaccess file not doing the url rewrite. The hoster told me they use ISAPI_REWRITE 3 for IIS. Finally got it working by commenting out line 113 "RewriteCond %{REQUEST_URI} "^/~?[-_.a-zA-Z0-9/]*$"", and now it's all working fine. I don't understand the possible negative consequences by commenting out this line?