Unable to upload an attachment in RoundCube: The uploaded file exceeds the maximum size

Symptoms

1. Unable to upload an attachment in RoundCube:

PLESK_ERROR: The uploaded file exceeds the maximum size

2. Instructions from Cannot attach files in Roundcube: "The uploaded file exceeds the maximum size did not help to resolve the issue.

3. The following output is shown when executing PHP handler with RoundCube PHP configuration file:

# /usr/bin/php -c  /etc/psa-webmail/roundcube/php.ini -i
PHP:  syntax error, unexpected TC_CONSTANT in /etc/psa-webmail/roundcube/php.ini on line 18

4. There is the following 18th line in /etc/psa-webmail/roundcube/php.ini :

CONFIG_TEXT: open_basedir = no value

Cause

Incorrect syntax in  RoundCube PHP configuration file.

Resolution

1. Access the server via SSH.

2. Open the RoundCube PHP configuration file with a text editor:

# nano /etc/psa-webmail/roundcube/php.ini

3. Edit the incorrect line. Change from:

CONFIG_TEXT: open_basedir = no value

to:

CONFIG_TEXT: open_basedir = none