症状

1. Attachment contains an umlaut or other special character, e.g. äüö.xls

2. Attachment deletion fails with "Not Permitted" page even though user has sufficient permission:

   Not Permitted
   You are not permitted to perform this operation.

3. Viewing or editing the properties of the attachment leads to a System Error page with the following stacktrace:

   java.lang.NullPointerException
    at com.atlassian.confluence.pages.actions.MoveAttachmentAction.bootstrap(MoveAttachmentAction.java:112) 

原因

• The application server URL encoding is not set to UTF-8.

• The URL encoding attribute is written wrongly or is incorrectly cased, hence Tomcat doesn't understand and pick it up. For example: URIencoding is wrong because it should have an uppercase E, and URlEncoding is wrong because it has a lowercase L instead of an uppercase I. The correct attribute is URIEncoding. It should look like this:
  

  URIEncoding="UTF-8"

ソリューション

1. Set your application server URL encoding to UTF-8 as described here. For example, in Tomcat add URIEncoding="UTF-8" to the HTTP connector.
2. Confluence を再起動します。

You might need to apply this to all available connectors, too (e.g. AJP connector).