Steps to reproduce

1. Take owncloud 9.0.1.3 which has benn upgraded from 8.x
2. Have an Microsoft Active Directory setup as owncloud-LDAP (in my case: 2 active directory servers)
3. take an LDAP-User which never logged in to owncloud before
4. This only occurs when you have LDAP groups defined. without any group, this issue is not occuring.

Expected behaviour

The user should be able to login to the owncloud webpage and should get the "welcome message" and should be able to handle files.
On the webserver's file system there should be a new directory created with the directory name = his username.

Actual behaviour

The user enters his passowrd and tries to logon. He receives the webserver error 500.
The apache logfile shows the following entry:
PHP Fatal error: Call to a member function file_exists() on a non-object in /var/www/owncloud/lib/private/files/filesystem.php on line 693

On the file system of the webserver, OC-Data-directory, there has no new sub-directory for this user been created.

If I create a user in owncloud and logon with this user, everything works fine (user not coming from active directory / LDAP).
If I take a user which has been created from actie directory/LDAP in owncloud version 8.x, everything works fine (the user fodler in data directory has been created correctly under 8.x)

Server configuration

Operating system: ubuntu 14.04

Web server: apache 2.4.7

Database: mysql

PHP version: 5.5.9

ownCloud version: (see ownCloud admin page) 9.0.1.3

Updated from an older ownCloud or fresh install: updated from 8.x (took each single step, no version left out)

Where did you install ownCloud from: download tar file from owncloud.org

Signing status (ownCloud 9.0 and above):
no idea what I should enter here... please reply what I should add here... sorry

Login as admin user into your ownCloud and access 
http://example.com/index.php/settings/integrity/failed 
paste the results here.
No errors have been found.

List of activated apps:

Enabled:

• activity: 2.2.1
• comments: 0.2
• dav: 0.1.6
• federatedfilesharing: 0.1.0
• federation: 0.0.4
• files: 1.4.4
• files_external: 0.5.2
• files_sharing: 0.9.1
• files_texteditor: 2.1
• files_trashbin: 0.8.0
• files_versions: 1.2.0
• files_videoplayer: 0.9.8
• firstrunwizard: 1.1
• notifications: 0.2.3
• provisioning_api: 0.4.1
• systemtags: 0.2
• templateeditor: 0.1
• updatenotification: 0.1.0
• user_external: 0.4
• user_ldap: 0.8.0
  Disabled:
• encryption
• external
• files_pdfviewer
• gallery

The content of config/config.php:

{
"system": {
"instanceid": "513af407e8f2d",
"passwordsalt": "_REMOVED SENSITIVE VALUE",
"datadirectory": "/mnt/sdb1/owncloud_data",
"dbtype": "mysql",
"version": "9.0.1.3",
"installed": true,
"memcache.local": "\OC\Memcache\APC",
"ldapIgnoreNamingRules": false,
"loglevel": 1,
"maintenance": false,
"theme": "",
"trusted_domains": [
"abc.domain.com",
"xyz.domain.com"
],
"share_folder": "/Shared",
"secret": "_REMOVED SENSITIVE VALUE",
"forcessl": true,
"forceSSLforSubdomains": true,
"mail_from_address": "it",
"mail_smtpmode": "smtp",
"mail_domain": "domain.com",
"mail_smtphost": "10.180.1.203",
"mail_smtpport": "25",
"dbname": "owncloud",
"dbhost": "10.180.1.48",
"dbuser": "_REMOVED SENSITIVE VALUE",
"dbpassword": "_REMOVED SENSITIVE VALUE"
}
}

Are you using external storage, if yes which one: external = local disk on same server, just the data directory outside the webserver directory. see config.

Are you using encryption: no

Are you using an external user-backend, if yes which one: ActiveDirectory

LDAP configuration (delete this part if not used)

+-------------------------------+----------------------------------------------------------------------------------------------------------------------------------------------------------------+
| Configuration | s02 |
+-------------------------------+----------------------------------------------------------------------------------------------------------------------------------------------------------------+
| hasMemberOfFilterSupport | 1 |
| hasPagedResultSupport | |
| homeFolderNamingRule | |
| lastJpegPhotoLookup | 0 |
| ldapAgentName | CN=LDAP-Anmeldeuser,OU=Service-User,OU=Benutzer,OU=Organisation,DC=domain,DC=com |
| ldapAgentPassword | *** |
| ldapAttributesForGroupSearch | |
| ldapAttributesForUserSearch | |
| ldapBackupHost | |
| ldapBackupPort | |
| ldapBase | DC=domain,DC=com |
| ldapBaseGroups | DC=domain,DC=com |
| ldapBaseUsers | DC=domain,DC=com |
| ldapCacheTTL | 600 |
| ldapConfigurationActive | 1 |
| ldapDynamicGroupMemberURL | |
| ldapEmailAttribute | mail |
| ldapExperiencedAdmin | 0 |
| ldapExpertUUIDGroupAttr | |
| ldapExpertUUIDUserAttr | |
| ldapExpertUsernameAttr | |
| ldapGroupDisplayName | cn |
| ldapGroupFilter | (&(|(objectclass=group))) |
| ldapGroupFilterGroups | |
| ldapGroupFilterMode | 0 |
| ldapGroupFilterObjectclass | group |
| ldapGroupMemberAssocAttr | member |
| ldapHost | 10.180.1.201 |
| ldapIgnoreNamingRules | |
| ldapLoginFilter | (&(&(|(objectclass=organizationalPerson)(objectclass=person)(objectclass=user)))(|(samaccountname=%uid)(|(mailPrimaryAddress=%uid)(mail=%uid)))) |
| ldapLoginFilterAttributes | |
| ldapLoginFilterEmail | 1 |
| ldapLoginFilterMode | 0 |
| ldapLoginFilterUsername | 1 |
| ldapNestedGroups | 0 |
| ldapOverrideMainServer | |
| ldapPagingSize | 500 |
| ldapPort | 389 |
| ldapQuotaAttribute | |
| ldapQuotaDefault | |
| ldapTLS | 0 |
| ldapUserDisplayName | displayname |
| ldapUserDisplayName2 | |
| ldapUserFilter | (&(|(objectclass=organizationalPerson)(objectclass=person)(objectclass=user))(|(|(memberof=CN=Domänen-Benutzer,CN=Users,DC=domain,DC=com)(primaryGroupID=513)))) |
| ldapUserFilterGroups | Domänen-Benutzer |
| ldapUserFilterMode | 0 |
| ldapUserFilterObjectclass | organizationalPerson;person;user |
| ldapUuidGroupAttribute | auto |
| ldapUuidUserAttribute | auto |
| turnOffCertCheck | 0 |
| useMemberOfToDetectMembership | 1 |
+-------------------------------+----------------------------------------------------------------------------------------------------------------------------------------------------------------+
+-------------------------------+-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------+
| Configuration | s03 |
+-------------------------------+-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------+
| hasMemberOfFilterSupport | 1 |
| hasPagedResultSupport | |
| homeFolderNamingRule | |
| lastJpegPhotoLookup | 0 |
| ldapAgentName | CN=LDAP-Anmeldeuser,OU=Service-User,OU=Benutzer,OU=Organisation,DC=domain,DC=com|
| ldapAgentPassword | *** |
| ldapAttributesForGroupSearch | |
| ldapAttributesForUserSearch | |
| ldapBackupHost | |
| ldapBackupPort | |
| ldapBase | DC=domain,DC=com|
| ldapBaseGroups | DC=domain,DC=com |
| ldapBaseUsers | DC=domain,DC=com |
| ldapCacheTTL | 600 |
| ldapConfigurationActive | 1 |
| ldapDynamicGroupMemberURL | |
| ldapEmailAttribute | |
| ldapExperiencedAdmin | 0 |
| ldapExpertUUIDGroupAttr | |
| ldapExpertUUIDUserAttr | |
| ldapExpertUsernameAttr | |
| ldapGroupDisplayName | cn |
| ldapGroupFilter | |
| ldapGroupFilterGroups | |
| ldapGroupFilterMode | 0 |
| ldapGroupFilterObjectclass | |
| ldapGroupMemberAssocAttr | uniqueMember |
| ldapHost | 10.180.1.202 |
| ldapIgnoreNamingRules | |
| ldapLoginFilter | (&(&(|(objectclass=inetOrgPerson)(objectclass=organizationalPerson)(objectclass=person)(objectclass=user)))(|(samaccountname=%uid)(|(mailPrimaryAddress=%uid)(mail=%uid)))) |
| ldapLoginFilterAttributes | |
| ldapLoginFilterEmail | 1 |
| ldapLoginFilterMode | 0 |
| ldapLoginFilterUsername | 1 |
| ldapNestedGroups | 0 |
| ldapOverrideMainServer | |
| ldapPagingSize | 500 |
| ldapPort | 389 |
| ldapQuotaAttribute | |
| ldapQuotaDefault | |
| ldapTLS | 0 |
| ldapUserDisplayName | displayname |
| ldapUserDisplayName2 | |
| ldapUserFilter | (&(|(objectclass=inetOrgPerson)(objectclass=organizationalPerson)(objectclass=person)(objectclass=user))) |
| ldapUserFilterGroups | |
| ldapUserFilterMode | 0 |
| ldapUserFilterObjectclass | organizationalPerson;person;user |
| ldapUuidGroupAttribute | auto |
| ldapUuidUserAttribute | auto |
| turnOffCertCheck | 0 |
| useMemberOfToDetectMembership | 1 |
+-------------------------------+-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------+

Client configuration

Browser: Firefox, Chrome, Internet Explorer

Operating system: Windows 8.1, Windows 7

Logs

Web server error log

[Tue May 03 16:05:40.213672 2016] [:error] [pid 5464] [client 10.180.18.26:44403] PHP Fatal error: Call to a member function file_exists() on a non-object in /var/www/owncloud/lib/private/files/filesystem.php on line 693
[Tue May 03 16:05:47.039942 2016] [:error] [pid 5454] [client 10.180.18.26:44407] PHP Fatal error: Call to a member function file_exists() on a non-object in /var/www/owncloud/lib/private/files/filesystem.php on line 693
[Tue May 03 16:05:53.116388 2016] [:error] [pid 5452] [client 10.180.18.26:44488] PHP Fatal error: Call to a member function file_exists() on a non-object in /var/www/owncloud/lib/private/files/filesystem.php on line 693
[Tue May 03 16:19:55.750866 2016] [:error] [pid 5455] [client 10.180.5.54:45340] PHP Fatal error: Call to a member function file_exists() on a non-object in /var/www/owncloud/lib/private/files/filesystem.php on line 693

Owncloud-Log

{"reqId":"rGfG5VjBMEWwH91sZmYQ","remoteAddr":"10.180.5.54","app":"user_ldap","message":"Looking for cookie L/O 500/0","level":1,"time":"2016-05-03T14:19:54+00:00","method":"GET","url":"/cron.php","user":"--"}
{"reqId":"rGfG5VjBMEWwH91sZmYQ","remoteAddr":"10.180.5.54","app":"user_ldap","message":"No paged search for us, Cpt., Limit 500 Offset 500","level":1,"time":"2016-05-03T14:19:54+00:00","method":"GET","url":"/cron.php","user":"--"}
{"reqId":"rGfG5VjBMEWwH91sZmYQ","remoteAddr":"10.180.5.54","app":"user_ldap","message":"Paged search was not available","level":1,"time":"2016-05-03T14:19:54+00:00","method":"GET","url":"/cron.php","user":"--"}
{"reqId":"rGfG5VjBMEWwH91sZmYQ","remoteAddr":"10.180.5.54","app":"user_ldap","message":"Looking for cookie L/O 500/0","level":1,"time":"2016-05-03T14:19:55+00:00","method":"GET","url":"/cron.php","user":"--"}
{"reqId":"rGfG5VjBMEWwH91sZmYQ","remoteAddr":"10.180.5.54","app":"user_ldap","message":"No paged search for us, Cpt., Limit 500 Offset 500","level":1,"time":"2016-05-03T14:19:55+00:00","method":"GET","url":"/cron.php","user":"--"}
{"reqId":"rGfG5VjBMEWwH91sZmYQ","remoteAddr":"10.180.5.54","app":"user_ldap","message":"Paged search was not available","level":1,"time":"2016-05-03T14:19:55+00:00","method":"GET","url":"/cron.php","user":"--"}
{"reqId":"rGfG5VjBMEWwH91sZmYQ","remoteAddr":"10.180.5.54","app":"PHP","message":"Call to a member function file_exists() on a non-object at /var/www/owncloud/lib/private/files/filesystem.php#693","level":3,"time":"2016-05-03T14:19:55+00:00","method":"GET","url":"/cron.php","user":"--"}