If you have trouble installing, configuring or maintaining Nextcloud, please refer to our community support channels:
- The Nextcloud IRC chat channel
irc://#firstname.lastname@example.org freenode.net, also accessible via webchat
Please understand that all these channels essentially consist of users like you helping each other out. Consider helping others out where you can, to contribute back for the help you get. This is the only way to keep a community like Nextcloud healthy and sustainable!
If you are using Nextcloud in a business or otherwise large scale deployment, note that Nextcloud GmbH offers commercial support options.
If you think you have found a bug in Nextcloud, please:
- Search for a solution (see the options above)
- Double-check your configuration
Check the Nextcloud System requirements, especially supported browser versions.
When you see warnings about
code integrity, refer to Code signing.
Disable 3rdparty / non-shipped apps¶
It might be possible that 3rd party / non-shipped apps are causing various different issues. Always disable 3rd party apps before upgrades, and for troubleshooting. Please refer to the Apps commands on how to disable an app from command line.
In a standard Nextcloud installation the log level is set to
Normal. To find
any issues you need to raise the log level to
All in your
file, or to Everything on your Nextcloud Admin page. Please see
Logging configuration for more information on
these log levels.
config/config.php and change
'debug' => false, to
'debug' => true, Be sure to change it back when you are finished.
The logfile of Nextcloud is located in the data directory
PHP version and information¶
You will need to know your PHP version and configurations. To do this, create a
plain-text file named phpinfo.php and place it in your Web root, for
/var/www/html/phpinfo.php. (Your Web root may be in a different
location; your Linux distribution documentation will tell you where.) This file
contains just this line:
<?php phpinfo(); ?>
Open this file in a Web browser by pointing your browser to
Your PHP version is at the top, and the rest of the page contains abundant
system information such as active modules, active
.ini files, and much more.
When you are finished reviewing your information you must delete
phpinfo.php, or move it outside of your Web directory, because it is a
security risk to expose such sensitive data.
Debugging sync issues¶
The data directory on the server is exclusive to Nextcloud and must not be modified manually.
Disregarding this can lead to unwanted behaviors like:
- Problems with sync clients
- Undetected changes due to caching in the database
If you need to directly upload files from the same server please use a WebDAV
command line client like
cadaver to upload files to the WebDAV interface at:
Common problems / error messages¶
Some common problems / error messages found in your logfiles as described above:
SQLSTATE[HY000]  Too many connections-> You need to increase the connection limit of your database, please refer to the manual of your database for more information.
SQLSTATE[HY000]: General error: 5 database is locked-> You’re using
SQLitewhich can’t handle a lot of parallel requests. Please consider converting to another database like described in Converting database type.
SQLSTATE[HY000]: General error: 2006 MySQL server has gone away-> Please refer to Troubleshooting for more information.
SQLSTATE[HY000]  No such file or directory-> There is a problem accessing your SQLite database file in your data directory (
data/nextcloud.db). Please check the permissions of this folder/file or if it exists at all. If you’re using MySQL please start your database.
Connection closed / Operation cancelled-> This could be caused by wrong
KeepAlivesettings within your Apache config. Make sure that
KeepAliveis set to
Onand also try to raise the limits of
No basic authentication headers were found-> This error is shown in your
data/nextcloud.logfile. Some Apache modules like
mod_proxy_fcgiare not passing the needed authentication headers to PHP and so the login to Nextcloud via WebDAV, CalDAV and CardDAV clients is failing. Information on how to correctly configure your environment can be found at the forums.
Troubleshooting Web server and PHP problems¶
When having issues the first step is to check the logfiles provided by PHP, the Web server and Nextcloud itself.
In the following the paths to the logfiles of a default Debian installation running Apache2 with mod_php is assumed. On other Web servers, Linux distros or operating systems they can differ.
- The logfile of Apache2 is located in
- The logfile of PHP can be configured in your
/etc/php5/apache2/php.ini. You need to set the directive
Onand choose the path to store the logfile in the
error_logdirective. After those changes you need to restart your Web server.
- The logfile of Nextcloud is located in the data directory
Web server and PHP modules¶
Lighttpd is not supported with Nextcloud, and some Nextcloud features may not work at all on Lighttpd.
There are some Web server or PHP modules which are known to cause various problems like broken up-/downloads. The following shows a draft overview of these modules:
- libapache2-mod-php5filter (use libapache2-mod-php5 instead)
- mod_spdy together with libapache2-mod-php5 / mod_php (use fcgi or php-fpm instead)
- mod_xsendfile / X-Sendfile (causing broken downloads if not configured correctly)
- X-Sendfile (causing broken downloads if not configured correctly)
Nextcloud uses SabreDAV, and the SabreDAV documentation is comprehensive and helpful.
- SabreDAV FAQ
- Web servers (Lists lighttpd as not recommended)
- Working with large files (Shows a PHP bug in older SabreDAV versions and information for mod_security problems)
- 0 byte files (Reasons for empty files on the server)
- Clients (A comprehensive list of WebDAV clients, and possible problems with each one)
- Finder, OS X’s built-in WebDAV client (Describes problems with Finder on various Web servers)
There is also a well maintained FAQ thread available at the ownCloud Forums which contains various additional information about WebDAV problems.
Some clients - especially on iOS/macOS - have problems finding the proper sync URL, even when explicitly configured to use it.
If you want to use CalDAV or CardDAV clients or other clients that require service discovery together with Nextcloud it is important to have a correct working setup of the following URLs:
Those need to be redirecting your clients to the correct endpoints. If Nextcloud is running at the document root of your Web server the correct URL is:
https://example.com/remote.php/dav for CardDAV and CalDAV and
and if running in a subfolder like
For the first case the
.htaccess file shipped with Nextcloud should do
this work for you when you’re running Apache. You need to make sure that your
Web server is using this file. Additionally, you need the mod_rewrite Apache
module installed to process these redirects. When running Nginx please refer to
If your Nextcloud instance is installed in a subfolder called
you’re running Apache create or edit the
.htaccess file within the
document root of your Web server and add the following lines:
RewriteRule ^\.well-known/host-meta /nextcloud/public.php?service=host-meta [QSA,L] RewriteRule ^\.well-known/host-meta\.json /nextcloud/public.php?service=host-meta-json [QSA,L] RewriteRule ^\.well-known/webfinger /nextcloud/public.php?service=webfinger [QSA,L] RewriteRule ^\.well-known/carddav /nextcloud/remote.php/dav/ [R=301,L] RewriteRule ^\.well-known/caldav /nextcloud/remote.php/dav/ [R=301,L]
Make sure to change /nextcloud to the actual subfolder your Nextcloud instance is running in.
Now change the URL in the client settings to just use:
instead of e.g.
There are also several techniques to remedy this, which are described extensively at the Sabre DAV website.
Troubleshooting contacts & calendar¶
Unable to update contacts or events¶
If you get an error like:
PATCH https://example.com/remote.php/dav HTTP/1.0 501 Not Implemented
it is likely caused by one of the following reasons:
- Using Pound reverse-proxy/load balancer
- As of writing this Pound doesn’t support the HTTP/1.1 verb. Pound is easily patched to support HTTP/1.1.
- Misconfigured Web server
- Your Web server is misconfigured and blocks the needed DAV methods. Please refer to Troubleshooting WebDAV above for troubleshooting steps.