Horde Administrator's FAQ

Troubleshooting and Common Problems

A blank white screen appears or the browser opens a download dialog instead of displaying the screen

In order to get an idea of what really happened, take a look in the web server's error log, in which more verbose errors should be found, at least if you properly configured error logging in your PHP setup.

Possible reasons could be a fatal PHP error, not being displayed to the browser (which is a good thing on production systems, but bad if you are trying to hunt down a problem)¹, or a segfaulting server process (happens most times in the c-client library while using IMP). If you correctly configured your web server and PHP to log all errors, you should find more information in your web server's or PHP's log files, or whereever you log the errors (syslog etc.).

Another place to see is the Horde log which is being configured in Horde's setup. By default Horde is logging to the file /tmp/horde.log.

After logging in users are immediately thrown back to the login screen

If looking at the Horde log file you see a successful login attempt, and the login screen doesn't contain any error message.

This happens if sessions aren't working properly for some reason. These are possible troubleshooting steps and their solutions:

Check that PHP sessions are working at all using the sessions test on the /horde/test.php test script.

If not, make sure that your browser accepts cookies. Otherwise check http://www.php.net/manual/en/ref.session.php for more information and hints.

Try logging in with the default PHP session handler if you configured a custom session handler in Horde's setup.

If this works, something is broken with your custom session handler setup or backend. Continue troubleshooting there.

If using Horde 3.1.2 or later, change the configuration to allow non-cookie, url-based sessions.

If this works, cookies aren't stored in your browser. This could be caused by the browser configuration or a faulty session cookie setup, see the next point. If you already locked yourself out of Horde, edit the configuration file horde/config/conf.php manually and set $conf['session']['use_only_cookies'] = false;.

Make sure that you are using the correct cookie domain and path settings in Horde's setup.

Cookies are not stored in the browser if you don't use a FQDN (fully qualified domain name), e.g. http://localhost/horde/, or if the specified cookie path (/horde by default) doesn't match the webroot of your Horde installation, e.g. http://webmail.example.org/, http://www.example.org/horde-3.1.2/.

After logging in the message "Last login: Never" is displayed. Always.

You didn't configure a permanent preference backend like SQL or LDAP. Preference backends are used to store user settings and personal stuff like the last login time. As an administrator go the the setup screen for Horde, select the Preference System tab, and enter the necessary settings. The PHP Sessions backend does not store the user settings permanently. You might also need to create some storage resource in the backend of your choice, e.g. a table in your SQL database or a scheme in your LDAP directory. But this is covered in the installation documentation.

When you are using preferences data from Horde 2.x with Horde 3.0, you have to delete all last_login preferences, as mentioned in the upgrading instructions. This could be done with an SQL statement like:

DELETE FROM horde_prefs WHERE pref_name = 'last_login';

Common error messages

"Call to undefined function: _( )"

This error occurs when PHP is not compiled with gettext support. As of version Horde 2.0, PHP needs to be compiled with gettext support. Rebuild PHP with the --with-gettext option to configure, or if using RPM's install the php-gettext RPM. (_() is a synonym for gettext() in PHP.)

"Document contains no data"

The browser error message, "Document contains no data", only tells you that nothing was sent from the web server to the browser. In other words, something went quite wrong, yet you've no idea what.

See A blank white screen appears

"Failed opening test.php for inclusion"

The set_perms.sh script and some packaged distributions change the permissions on the test.php script so that it can't be run. This increases the security of your web server by not revealing to intruders information about how PHP is compiled/configured or what Horde applications are installed. To use the script while setting up Horde, add read permission for your web server to the script:

chmod +r horde/test.php

Remember to remove read permission (chmod a-r) from the file when you have finished testing.

"Fatal error: Allowed memory size of ### bytes exhausted..."

Either recompile PHP without the --enable-memory-limit option, or increase the value of memory_limit in your php.ini file.

Note that when making a change to your php.ini file you will probably need to restart your web server software in order for the changes to become active.

"Fatal error: Undefined class name 'log' in ..."

"Failed opening 'Log.php' for inclusion"

Your PHP PEAR implementation is missing the PEAR Log package. This is a common problem with the PHP 4.2.1 PEAR for example. You can install it via the network if you have a standalone php/pear command. See the file horde/docs/INSTALL for more information on how to install the required PEAR packages this way. Otherwise you can download Log and other required PEAR packages (e.g. from http://pear.php.net/get/Log) and manually install them inside your PEAR directory. You may also need to install the modules Mail_Mime and Net_Socket. Horde's test.php script will give you an overview of which required PEAR packages are installed and which are missing.

For more detailed instructions on installing PEAR modules, see the PEAR documentation at http://pear.php.net/manual/.

"Only variable references should be returned by reference"

"Only variables can be passed by reference"

These messages appear after upgrading to PHP 4.4 or PHP 5.1. These PHP versions raise notices about reference usage that older version accepted happily. Only Horde 3.x and the H3 application versions are fixed to not cause these messages, so either upgrade to the latest versions, or set your error reporting level in PHP to exclude E_NOTICE level messages.

E.g. in php.ini:

error_reporting = E_ALL & ~E_NOTICE

You can also turn off the display of error reporting entirely, although this might cause problems diagnosing problems in the future. After you get a good, working installation you can turn off the display of error messages to the browser and just log them.

E.g. in php.ini:

display_errors = Off

log_errors = On

error_log = syslog ; goes to NT event log on NT-based machines

; error_log = /var/log/php_error

Note that when making a change to your php.ini file you will probably need to restart your web server software in order for the changes to become active.

"output handler 'ob_gzhandler' cannot be used twice in..."

[Horde 2.x]: You enabled output compression in both your php.ini configuration file and in your horde configuration file (either horde/config/horde.php or horde/config/conf.php). Disable it in one of these two locations. Current Horde versions check to see if the gz output buffer is in place before adding it again.

"top.opener.parent is not an object"

This error is the result of a bug in Internet Explorer. Stuart suggests that the following commands (executed on the Windows system on which Internet Explorer is installed) will solve the problem:

regsvr32 c:\windows\system32\actxprxy.dll

regsvr32 c:\windows\system32\shdocvw.dll

The FAQ maintainer has not tested the above! Make sure you have a backup of your system before playing with deep Windows magic.

"Unable to load dynamic library php_whatever.dll - The specified module could not be found."

This error message is a misrepresentation of the actual problem. Often occurs when some dependency needed for php_whatever.dll is missing.e.g. need to copy iconv.dll (from the dlls folder under to the php install directory) to windows\system32 to get php_gettext.dll to load.

"Unable to open VFS file for writing"

If you see this message from kronolith or trean (or any other application hat uses crontabs) you are running a crontab script as a different user as you did in the first run. Adjust your crontab (running it as same user as the webserver is a good idea) and also change the ownship of <your_vfs_root>/.horde.

"undefined function: bindtextdomain()"

This error occurs when PHP is not compiled with gettext support. As of Horde 2.0, PHP needs to be compiled with gettext support. Rebuild PHP with the --with-gettext option to configure, or if using RPM's install the php-gettext RPM.

"undefined function: imap_open"

This error is the result of using IMP without compiling IMAP support into PHP. Be sure that your PHP installation supports IMAP, and rebuild it with the --with-imap flag to configure if it does not (or install the php-imap RPM in an RPM installation).

"imap_utf7_decode: Unexpected end of string"

"undefined function: imap_utf7_encode()"

This error most often occurs when IMP tries to use a folder name with an ampersand (&) in it. The easiest solution is to rename the folder to something without an ampersand in it (on the server, or with a different IMAP client).

The error can also occur if IMAP support has not been compiled into PHP. Ensure that your PHP installation supports IMAP.

"undefined function: mysql_connect()"

"undefined function: mysql_pconnect()"

This error occurs when IMP is configured to use MySQL, but PHP was not built with support for MySQL. Rebuild PHP, ensuring that MySQL support is compiled in, and that the line

extension = mysql.so

appears in your php.ini

"Warning: Unable to open '/tmp/...'" when attaching

On some systems (commonly Solaris and FreeBSD), the upload_tmp_dir setting in php.ini must be set to /var/tmp.

Note that when making a change to your php.ini file you will probably need to restart your web server software in order for the changes to become active.

Verifying Components

How can I tell if my Web server works?

Testing your webserver is straightforward: place a file containing some HTML (or even just some text) in the directory in which it expects to find its data (in Apache, DocumentRoot), and make the file world-readable. Start up the webserver if it is not already running, and in your browser, load

http://hostname.example.com/filename

(substituting the name of the server and the filename as appropriate). If you see the contents of the file, your web server is running. If you receive an error, check your web server's error log to see what went wrong.

How can I tell if PHP works?

The simplest way to test PHP is to create a file, phpinfo.php3, somewhere under your web server's document root, with the following contents:

<?php phpinfo() ?>

Upon accessing it with a browser, you should be presented with a summary of your PHP configuration. If you see the program text itself, your web server does not know to interpret the file with PHP.

How can I tell if Horde works?

Horde includes a PHP program which will test both your Horde and PHP installations. If you have horde installed in the usual location, point your browser at

http://hostname.example.com/horde/test.php

Verify the following from the information test.php offers:

• You are running a supported version of PHP.
  • Gettext support reads "Yes"
  • IMAP support reads "Yes"
  • If you plan on using MySQL, PostgreSQL, or LDAP, their "Support" lines read "Yes".
  • magic_quotes_runtime set to Off reads "Yes".
  • The session counter increments when the page is reloaded.
  • All the PEAR options return "Yes".

This page also may have links to test pages for other installed modules, and/or links to other PHP information pages available.

How can I tell if my IMAP server works?

The simplest way to test an IMAP server is to send mail to an account on the IMAP server, and then use a standard IMAP client like Netscape Mail, Outlook Express, PINE, mutt, or Eudora Pro to read the mail.

If you don't have a standard IMAP client handy, or if a standard client fails, you can telnet to port 143 of your IMAP server and try the following exchange (where "normal" server responses are emphasized):

* OK imap.example.com IMAP4rev1 v12.264 server ready

0 login yourusername yourpassword

0 OK LOGIN completed

0 logout

If you don't get OK LOGIN, then your server is probably misconfigured (unless you are using a specific authentication module such as Kerberos, in which case you will probably have to test it with a real IMAP client or the mtest program included with the UW-IMAP c-client distribution).

How can I tell if my database works?

The most straightforward way of testing your database is to create the Horde databases themselves; if the creation proceeds without error, then the database is probably functioning normally.

You can also use the following code, contributed by <chowes@ics.bc.ca>:

<html>

<head><title>DB Test</title></head>

<body>

This is a test:<br>

<?php

function test()

{

    if (!($db = mysql_connect('localhost','root','yourpassword'))) return 1;

    if (!mysql_query('create database testdb', $db)) return 2;

    if (!mysql_select_db('testdb', $db)) return 3;

    if (!mysql_db_query('testdb', 'create table testtest ( test char(60))', $db)) return 4;

    if (!mysql_db_query('testdb', 'insert into testtest values (\'hello world!\')', $db)) return 5;

    if (!($result = mysql_db_query('testdb', 'select * from testtest', $db))) return 6;

    if (mysql_num_rows($result) > 0) echo mysql_result($result, 0, 0);

    if (!mysql_db_query('testdb', 'delete from testtest', $db)) return 7;

    if (!mysql_query('drop database testdb', $db)) return 8;

    return 9;

}

$r = test();

echo "<br>result code = $r";

?>

</body>

</html>

Then, load the file with your browser. It will create a database, a table, and a row; put data into the row; then delete the row, the table, and the database. If successful, the output will read

This is a test: hello world!

result code=9

If it does not, at least you can see where it breaks, by matching the result code with the return statement in the program; the line on which the matching return statement lies is the one which failed. For instance, if result code=1, then mysql isn't running, or a bad host/username/password has been entered.

Troubleshooting IMP

Troubleshooting Turba

Troubleshooting Trean

Can't save bookmarks or categories.

This usually means one of the following:

• You didn't properly setup your Horde categories driver in horde/config/conf.php.
  • You set your categories driver to something which can't save data between sessions (like the "session" or "none" drivers.
  • You failed to create the needed category storage for your category setup (e.g. didn't create the database tables when using the sql driver).

Troubleshooting Chora

Why do I get a 404, Object not found error when clicking on any cvsroot subdirectories?

Some web servers do not support PATH_INFO, or have it disabled by default, in which case this problem will arise. Try to disable PATH_INFO usage by setting $conf['options']['use_path_info'] to false in horde/chora/config/conf.php.

Troubleshooting Vacation

I get an "501 5.6.0 Data format error" error in the replay from Vacation

I get the following error when setting up vacations using the Vacation Horde module.

The original message was received at Tue, 7 Mar 2006 17:03:07 +0100

from xxx.senderdomain.com [xxx.xxx.xxx.xxx]

   ----- The following addresses had permanent fatal errors -----

"|/usr/bin/vacation xxx"

    (reason: Data format error)

    (expanded from: <xxx@example.com>)

   ----- Transcript of session follows -----

501 5.6.0 Data format error

find this line of code in your "pathtohorde/vacation/lib/Drivers/forwards.php" file

// Try to change permissions, but ignore any errors.

$_vfs->changePermissions('', '.forward', '0600');

and append the following after this line

$_vfs->changePermissions('', '.vacation.db', '0640');

$_vfs->changePermissions('', '.vacation.msg', '0640');

$_vfs->changePermissions('', '.vacation.dir', '0640');

$_vfs->changePermissions('', '.vacation.pag', '0640');

delete your vacation entry using the vacation module and recreate it.

Problem should be solved.