Can't set external storage

[Bables55]

Steps to reproduce

1. Go Accout > Settings
2. Select External Storage from left pane.

Expected behaviour

The already set list is displayed.

Actual behaviour

Displayed "No external storage configured or you don't have the permission to configure them"

Next, when I disable the External Storage application, Nextcloud stops. And I can change the value of files_external from No to Yes in phpMyAdmin and restart Nextcloud. After that I have lost the item of external storage in the left pane when I look at the settings. It seems that actual external storage handling is done in this state. In other words, storage can not be set up.

Server configuration

Operating system:
CentOS 7.5
Web server:
nginx 1.13.8
Database:
MariaDB 5.5.56
PHP version:
PHP 7.1.18
Nextcloud version: (see Nextcloud admin page)
13.0.2
Updated from an older Nextcloud/ownCloud or fresh install:
Nextcloud 13.0.1
Where did you install Nextcloud from:
nextcloud.com
Signing status:

Signing status

No errors have been found.

List of activated apps:

App list

  - activity: 2.6.1
  - admin_audit: 1.3.0
  - announcementcenter: 3.2.1
  - apporder: 0.4.1
  - bruteforcesettings: 1.0.3
  - calendar: 1.6.1
  - comments: 1.3.0
  - contacts: 2.1.3
  - dav: 1.4.6
  - deck: 0.3.1
  - drawio: 0.8.9
  - encryption: 2.0.0
  - end_to_end_encryption: 1.0.5
  - federatedfilesharing: 1.3.1
  - federation: 1.3.0
  - files: 1.8.0
  - files_accesscontrol: 1.3.0
  - files_antivirus: 1.2.0
  - files_automatedtagging: 1.3.0
  - files_external: 1.4.1
  - files_frommail: 0.1.0
  - files_markdown: 2.0.4
  - files_pdfviewer: 1.2.1
  - files_rightclick: 0.8.4
  - files_sharing: 1.5.0
  - files_texteditor: 2.5.1
  - files_trashbin: 1.3.0
  - files_versions: 1.6.0
  - files_videoplayer: 1.2.0
  - gallery: 18.0.0
  - logreader: 2.0.0
  - lookup_server_connector: 1.1.0
  - mail: 0.8.1
  - mindmaps: 0.1.0
  - nextcloud_announcements: 1.2.0
  - notes: 2.3.2
  - notifications: 2.1.2
  - oauth2: 1.1.0
  - password_policy: 1.3.0
  - provisioning_api: 1.3.0
  - quicknotes: 0.1.3
  - ransomware_protection: 1.1.0
  - richdocuments: 2.0.8
  - serverinfo: 1.3.0
  - sharebymail: 1.3.0
  - sharepoint: 1.1.0
  - survey_client: 1.1.0
  - systemtags: 1.3.0
  - tasks: 0.9.6
  - theming: 1.4.5
  - twofactor_backupcodes: 1.2.3
  - updatenotification: 1.3.0
  - user_external: 0.4
  - workflowengine: 1.3.0
Disabled:
  - firstrunwizard
  - user_ldap

Nextcloud configuration:

Config report

    "system": {
        "debug": true,
        "instanceid": "***REMOVED SENSITIVE VALUE***",
        "passwordsalt": "***REMOVED SENSITIVE VALUE***",
        "secret": "***REMOVED SENSITIVE VALUE***",
        "trusted_domains": [
            "MY-DOMAIN",
        ],
        "datadirectory": "***REMOVED SENSITIVE VALUE***",
        "overwrite.cli.url": "https:\/\/MY-DOMAIN",
        "dbtype": "mysql",
        "version": "13.0.2.1",
        "dbname": "***REMOVED SENSITIVE VALUE***",
        "dbhost": "***REMOVED SENSITIVE VALUE***",
        "dbport": "",
        "dbtableprefix": "oc_",
        "mysql.utf8mb4": true,
        "dbuser": "***REMOVED SENSITIVE VALUE***",
        "dbpassword": "***REMOVED SENSITIVE VALUE***",
        "installed": true,
        "log_type": "file",
        "logtimezone": "Asia\/Tokyo",
        "loglevel": 2,
        "memcache.local": "\\OC\\Memcache\\APCu",
        "filelocking.enabled": true,
        "memcache.locking": "\\OC\\Memcache\\Redis",
        "redis": {
            "host": "***REMOVED SENSITIVE VALUE***",
            "port": 6379,
            "password": "***REMOVED SENSITIVE VALUE***"
        },
        "mail_smtpmode": "smtp",
        "mail_smtpauthtype": "LOGIN",
        "mail_smtpsecure": "ssl",
        "mail_from_address": "***REMOVED SENSITIVE VALUE***",
        "mail_domain": "***REMOVED SENSITIVE VALUE***",
        "mail_smtpauth": 1,
        "mail_smtphost": "***REMOVED SENSITIVE VALUE***",
        "mail_smtpport": "465",
        "mail_smtpname": "***REMOVED SENSITIVE VALUE***",
        "mail_smtppassword": "***REMOVED SENSITIVE VALUE***",
        "maintenance": false,
        "auth.bruteforce.protection.enabled": false,
        "versions_retention_obligation": "7,auto",
        "trashbin_retention_obligation": "auto",
        "defaultapp": "calendar",
        "theme": ""
    }

Are you using external storage, if yes which one: local/smb/sftp/...
SFTP
Are you using encryption: yes/no
Yes
Are you using an external user-backend, if yes which one: LDAP/ActiveDirectory/Webdav/...
WebDAV

Client configuration

Browser:
Firefox, Vivaldi
Operating system:
Windows 10

Logs

Web server error log

Web server error log

2018/05/31 11:33:29 [error] 2699#0: *6 access forbidden by rule, client: MY-GLOBAL-IP, server: MY-NEXTCLOUD-DOMAIN, request: "GET /data/.ocdata?t=1527734009920 HTTP/2.0", host: "MY-NEXTCLOUD-DOMAIN"
2018/05/31 11:33:34 [error] 2699#0: *6 access forbidden by rule, client: MY-GLOBAL-IP, server: MY-NEXTCLOUD-DOMAIN, request: "GET /data/.ocdata?t=1527734014087 HTTP/2.0", host: "MY-NEXTCLOUD-DOMAIN"
2018/05/31 11:34:13 [error] 2699#0: *6 access forbidden by rule, client: MY-GLOBAL-IP, server: MY-NEXTCLOUD-DOMAIN, request: "GET /data/.ocdata?t=1527734053682 HTTP/2.0", host: "MY-NEXTCLOUD-DOMAIN"
2018/05/31 11:49:24 [error] 12734#0: *419 access forbidden by rule, client: MY-GLOBAL-IP, server: MY-NEXTCLOUD-DOMAIN, request: "GET /data/.ocdata?t=1527734964588 HTTP/2.0", host: "MY-NEXTCLOUD-DOMAIN"
2018/05/31 11:49:42 [error] 12734#0: *419 access forbidden by rule, client: MY-GLOBAL-IP, server: MY-NEXTCLOUD-DOMAIN, request: "GET /data/.ocdata?t=1527734982637 HTTP/2.0", host: "MY-NEXTCLOUD-DOMAIN"
2018/05/31 11:49:51 [error] 12734#0: *419 access forbidden by rule, client: MY-GLOBAL-IP, server: MY-NEXTCLOUD-DOMAIN, request: "GET /data/.ocdata?t=1527734991007 HTTP/2.0", host: "MY-NEXTCLOUD-DOMAIN"
2018/05/31 11:59:50 [error] 12734#0: *419 access forbidden by rule, client: MY-GLOBAL-IP, server: MY-NEXTCLOUD-DOMAIN, request: "GET /data/.ocdata?t=1527735590720 HTTP/2.0", host: "MY-NEXTCLOUD-DOMAIN"
2018/05/31 12:17:59 [error] 12734#0: *419 access forbidden by rule, client: MY-GLOBAL-IP, server: MY-NEXTCLOUD-DOMAIN, request: "GET /data/.ocdata?t=1527736679023 HTTP/2.0", host: "MY-NEXTCLOUD-DOMAIN"
2018/05/31 12:18:04 [error] 12734#0: *419 access forbidden by rule, client: MY-GLOBAL-IP, server: MY-NEXTCLOUD-DOMAIN, request: "GET /data/.ocdata?t=1527736684688 HTTP/2.0", host: "MY-NEXTCLOUD-DOMAIN"

Nextcloud log (data/nextcloud.log)

Nextcloud log

Error	core	Can't get app storage, app files_external, user not logged in	

[Bables55]

I put files_external in the Nextcloud 13.0.1 package into the current Nextcloud. And I accessed Nextcloud with Web browser and processed the update. Thereafter, "External Storage" was displayed above and below the left pane of the setting.
I came to be able to use it. I noticed that this time I tried to add external storage for the first time in a while. I don't know if it was my only problem or coincidence.

[MorrisJobke]

We can't reproduce this. Seems to be a hiccup somewhere else. Please reach out if this happens again.