There are a few ways you can enable or disable debugging on your site. If you are able to login as an administrator and access the Site Administration block, then the easiest way is to go to Admin->Server->Debugging and set it there. There are several options - the most often recommended setting for debugging is 'ALL: Show all reasonable PHP debugging messages'. To disable debugging, simply set this to 'NONE: Do not show any errors or warnings.'.
File upload sizes are restricted in a number of ways - each one in the list restricts the following ones.
1. Firstly, there is a setting in Apache 2 which you may need to change. On Redhat this setting is very low by default, you can change the limit by adding or editing a line in Apache's /etc/httpd/conf/httpd.conf and/or /etc/httpd/conf.d/php.conf with the upload size in bytes (different operating systems may have these files in different locations):
2. PHP also has two more byte limits, which you can set in php.ini and sometimes in a .htaccess file:
php_value upload_max_filesize 50000000 php_value post_max_size 50000000
To convert from Bytes to Megabytes use this convertor
Please note that a server re-start may be required for the above changes to take effect.
3. Moodle has a site-wide limit called maxbytes that may be set in Administration > Configuration > Variables.
4. A limit may be set by teachers in the Course settings.
If a user is assigned a system role or a role in the course category context then the user has this role in ALL courses in that context. Thus users who are students or teachers at the category level appear as course participants in all courses in that category.
Please check Administration > Users > Permissions > Assign system roles and also the Assign roles link in course categories page and unassign users as necessary.
You can always go back and edit a resource or an activity that you have created in Moodle by choosing the 'update' option (once your editing is turned on). You can also move resources or activities in Moodle by choosing the up/down arrow icons beside the resource or activity (again, once your editing is turned on). If you have uploaded a document to the Moodle files section and wish to make a change, you will need to make the change locally and then re-upload the file. If you don't immediately see the changes, you may need to empty your cache/history in your web browser.
An identifier of the user's status in some context, for example Teacher, Student and Forum moderator
A description of a particular Moodle feature, for example moodle/blog:create
A setting for a capability - inherit, allow, prevent or prohibit
A "space" in Moodle, such as courses, activity modules or blocks