By default, Tomcat uses ISO-8859-1 character encoding when decoding URLs received from a browser. This can cause problems when Confluence's encoding is UTF-8, and you are using international characters in attachment or page names.

1. Edit conf/server.xml and find the line where the Coyote HTTP Connector is defined. It will look something like this, possibly with more parameters:

   <Connector port="8080"/>

2. Add a URIEncoding="UTF-8" property to the connector:

   <Connector port="8080" URIEncoding="UTF-8"/>

3. Restart Tomcat

If you are using mod_jk

You should apply the same URIEncoding parameter as above to the AJP connector if you are using mod_jk, and add the following option to your Apache mod_jk configuration:

<Connector port="8009" protocol="AJP/1.3" URIEncoding="UTF-8"/>

JkOptions +ForwardURICompatUnparsed

More information using Apache with Tomcat

For comprehensive examples of how to use Tomcat and Apache with Confluence, see Running Confluence behind Apache.