500 Internal Server Error ，求教怎么解决

[stchmim]

配置了webdav后 打开网站，输入账号密码后出现这种错误，以下是错误日志:
[Fri Jan 03 08:49:24.051968 2014] [authn_file:error] [pid 11340:tid 820] (OS 2)系统找不到指定的文件。 : [client 192.168.20.18:48768] AH01620: Could not open password file: D:/Apache Group/Apache24/user.ini

但我在 D:/Apache Group/Apache24/user.ini这个路径是有放账号密码文件的，

httpd-dav.conf的配置:
DavLockDB "D:/Apache Group/Apache24/var/DavLock"

Alias /upload "D:/Apache Group/Apache24/upload"

<Directory "D:/Apache Group/Apache24/upload">
Dav On
AuthType Basic
AuthName DAV-upload
AuthUserFile "D:/Apache Group/Apache24/user.ini"
AuthBasicProvider file
Require user admin
</Directory>
BrowserMatch "Microsoft Data Access Internet Publishing Provider" redirect-carefully
BrowserMatch "MS FrontPage" redirect-carefully
BrowserMatch "^WebDrive" redirect-carefully
BrowserMatch "^WebDAVFS/1.[01234]" redirect-carefully
BrowserMatch "^gnome-vfs/1.0" redirect-carefully
BrowserMatch "^XML Spy" redirect-carefully
BrowserMatch "^Dreamweaver-WebDAV-SCM1" redirect-carefully
BrowserMatch " Konqueror/4" redirect-carefully

请问是哪里出的问题，该怎么解决？