Blocking users is an action that sysops can perform upon users or IP addresses to prevent them from editing the wiki.
Blocking users is fairly straightforward, visit Special:BlockIP and follow these steps:
- IP address or username
- Enter in the username, IP address, or IP range to block in the field. If blocking a username, make sure to check the spelling since nonexistent users can be blocked as well. Instead of typing this information in manually, it is also possible to click on a block link in recent changes, contributions pages, or history pages, which will automatically fill in this field with the appropriate username or IP address. A block user link is also present in the toolbox when viewing User and User talk pages.
- Select when the block should expire from the drop-down menu.
- Other time
- Manually type in an expiration time of the block. When manually typing in a time, follow the GNU standard format.
- (Optional): the reason selected from the pre-defined reasons in the drop-down menu will be used as the message displayed to the blocked user when they try to edit.
- Other/additional reason
- (Optional): free form input filed that will combined with the <Reason:> reason specified, or show instead if no pre-defined reason is selected.
- Select additional block options
- (Optional) depending on if a username or IP is being blocked and other options that may have been enabled, some or all of these options will be displayed on the form.
- <ipbanononly>: this option is only available when blocking an IP address. When selected, registered users who try to edit using a blocked IP address will still be able to edit. Otherwise, they will be unable to edit as well.
- Prevent account creation: selecting this option will prevent the blocked username or IP address from creating new accounts.
- Automatically block the last IP address used by this user, and any subsequent IP addresses they try to edit from: this option is only available when blocking a username. When selected, the user's IP will become "autoblocked" (these show up as numbers such as #17 on the active block list) for a short period of time and any other IP addresses that the blocked user tries to edit from will be automatically blocked as well.
- Prevent user from sending email: this option is only available when blocking a username. When this option is selected, the user will be unable to use the Special:EmailUser interface.
- Watch this user's user and talk pages: when selected, this adds the blocked user's User page and User talk page to your watchlist.
Double-check everything you entered and click on Block this user. A message should appear saying if the block was successful or unsuccessful.
To unblock a username or IP address, go to the active block list and click on the unblock link next to the user or IP you wish to unblock. Then, enter in an reason (optional) and click on the unblock button. A message should appear saying if the unblock was successful or unsuccessful.
 What it means to be blocked
Blocked users are unable to edit pages, upload files, move pages, and perform other actions that additional user rights would grant. Effectively, this makes the wiki read only for those users. Sysops or others with access to the blocking and unblocking interface may still block and unblock others (including themselves) while blocked.