Attempting to mount Webdav drive to Windows gives "The folder you entered does not appear to be valid. Please choose another"

I have a Linux based httpd server setup with AD authentication that's working just fine for downloads. Users go to the website and are challenged for credentials. If you belong to a certain group you see all of it. If you're not in a specific group you see some of it.

A new requirement has been added where they want the users to be able to mount the website as a mounted drive via WebDav.

I tried to mount it and it failed with the error in the subject of the question. Tried to use "net use * https://my.url/webdav" and got: System error 67 has occurred (after being challenged for username and password).

I installed the cadaver linux client and can connect to the site from another server. I also installed Cygwin on my laptop with the cadaver client on it, and it connected just fine.

I had a colleague who's on a Mac try to connect using the Mac client and it connected, so it appears to be a Windows thing.

I also installed litmus and it appeared to pass the tests.

My google searching has so far also identified for me a few things I've tried unsuccessfully

• In the registry changing the value of HKLM\SYSTEM\CurrentControlSet\Services\WebClient\Parameters BasicAuthLevel key to 2 and restarting the WebClient service.
• In the same key, adding AuthForwardServerList and putting the URL there.

I have tried this with AuthType basic and AuthType digest (although digest didn't seem to want to work with AD)

Here's my (edited for privacy) config file:

<VirtualHost *:80>

ServerAdmin [email protected]
  ServerName myserver
  ServerAlias x.x.x.x
  DocumentRoot /

  LogLevel warn
#  LogLevel trace6
  ErrorLog "logs/interfaces_prd_webdav_error_log"
  CustomLog "|/usr/sbin/rotatelogs /var/log/httpd/webdav_access_log.%Y-%m-%d-%H_%M_%S 5M" "%t %h  \"%r\" %>s %b"

  LimitXMLRequestBody 131072
  DavLockDB /var/lib/dav/lockdb

# ************************************************************

  <Directory "/path/to/top/of/interfaces">
    AuthType Basic
    AuthName "Use Your Login"
    AuthBasicProvider ldap
    AuthLDAPURL "ldap://my_ad_server.local:389/ou=myou1,ou=clients,dc=mydc1,dc=local?mail?sub?(objectClass=*)"
    AuthLDAPGroupAttributeIsDN on
    AuthLDAPBindDN "searchuser"
    AuthLDAPBindPassword "searchuserpwd"
    Require valid-user
  </Directory>

  <Directory "/path/to/top/of/interfaces/secure">
    AuthType Basic
    AuthName "Use Your Login"
    AuthBasicProvider ldap
    AuthLDAPURL "ldap://my_ad_server.local:389/ou=myou1,ou=clients,dc=mydc1,dc=local?mail?sub?(objectClass=*)"
    AuthLDAPGroupAttributeIsDN on
    AuthLDAPBindDN "searchuser"
    AuthLDAPBindPassword "searchuserpwd"
    Satisfy all
    Require ldap-group CN=SecureGroup,OU=mygroup,OU=myou1,OU=Clients,DC=mydc1,DC=local
  </Directory>

  Alias /files /path/to/top/of/interfaces

  <Location /files>
    Dav on
    Options +Indexes
  </Location>

</VirtualHost>

Anyone have any insights on this?