1. Login as an admin user
2. Go to your Contol Panel
3. Choose Syndication
   
4. Click Edit beside the feed you need to filter a blog from
5. Scroll down and find the blog(s) you want to fliter out
6. Click the dropdown and choose “get filtered out” as shown below repeating for each blog you want to filter out
   
7. Click the Save Changes button

Filtering out these blogs will not remove them from the current feed however. It only prevents them from being syndicated from this point forward. To actually remove posts from the current feed you need to delete offensive syndicated posts.

Reminder, once you delete a blog it cannot be restored in the admin screens. It can only be restored from a database backup.

1. Login as an admin user
2. Go to your Contol Panel
3. Choose Site Admin
4. Choose Blogs as shown
   
5. Deleting 1 Blog Only
   1. Enter that blog name into the search user box and click Search
   2. Once that blog is displayed, click Delete on the right hand side of the screen for the user you want to delete.
6. Deleting multiple Blogs
   1. Check the box beside the blogs you want to delete – As a reminder here do not hit next or move to another page. You can only delete blogs from the current list
   2. Select the Delete box below the user list
      
   3. Click the Apply changes button as shown in the above image.

1. Login as an admin user
2. Go to your Contol Panel
3. Choose Site Admin
4. Choose Users
5. Check the box beside the user(s) you want to mark as spammers – As a reminder here do not hit next or move to another page. You can only mark users from the current list
6. Select the Mark as Spammers box below the user list
7. Click the Apply Changes button

To reverse this process, follow the same steps as above, but choose Not Spam instead.

1. Login as an admin user
2. Go to your Contol Panel
3. Choose Site Admin
4. Choose Users
5. Delete 1 User
   1. Enter that user name into the search user box and click Search
   2. Once that user is displayed, click Delete on the right hand side of the screen for the user you want to delete.
6. Delete multiple users
   1. Check the boxes beside the users you want to delete – As a reminder here do not hit next or move to another page. You can only delete users from the current list
   2. Select the Delete box below the user list
   3. Click the Apply Changes button

• Blog Names Deny List
• Email Domains Deny List

As I started, I realized this will be a long post and contain other useful tips that apply to normal maintenance of the site. Because of that I am going write multiple posts and then tie them all together here. The topics will be as follows:

• How to delete a user?
• How to mark a user as a spammer?
• How to delete a blog?
• How to mark blogs as spammers?
• How to block blog registrations of offensive/spam words?
• How to Ban Specified Email Domains From Registering?
• How to delete offensive syndicated posts?
• How to filter out a blog from Syndication?
• How to filter out keywords in blog titles from the main page?

As I write each post, I will link it here.

XML Parsing Error: xml declaration not at start of external entity

I have now, multiple times. It is something that is so easy to cause without even knowing how it happened or that it happened at all for hours or days.

We use WordPress MU here at Blogivists running on a Linux server. On the main page we have a feed that displays the latest posts from all of the blogivists blogs. Yesterday, we discovered our feed was broken and displaying the error shown above. I had seen this error before when securing the website.

I recognized it immediately as being blank lines in the code outside the php tags of . The problem becomes finding the errant code. If you don’t have shell access you will have to go through each file you have changed to find the error. With shell access the task becomes a little easier. I intend to make it even easier for you.

I started by doing the following in the webroot of the website:

find . -mtime -1 -name \*.php

This gave me a list of all files that had been changed in the past 24 hours. I then stepped through each file looking for the problem. This was a tedious and slow process. I started with files in wp-content/plugins and wp-includes. I had no luck.

Next I wrote a quick script that printed the first 2 and last 2 lines of each php file. I then worked my way through the list and again found nothing.

I assumed at this point that something was getting printed incorrectly. I added print statements throughout the feed building code (FeedWordPress) until it was obvious that my first thought was correct, a file had whitespace before or after the php tags.

I reran the find command from earlier. At this point I started checking the themes themselves. I had skipped those earlier since I did not think theme templates would have an effect on the feed building. I discovered themes do have an effect, particularly since the theme that caused the problem was the main page theme. I finally discovered the functions.php file had been edited and 2 blank lines had been placed at the top of the file before the <?php. I removed those and the feed was working properly again.

Now, to make this easier for everyone and myself when this happens again. I wrote a script that will run through every php file and check the to make sure there is no whitespace before the starting tag. As a side note here, you can remove the ending tag ?> to eliminate that issue, however it won’t prevent the leading whitespace issue. I don’t do that because I think it is bad coding style to not close all tags.

You can download a gzip file that contains the test files and script source by right clicking and choosing Save Link As on the following link (Check Whitespace Download). These are written for Linux, but could be modified for Windows is you wish. Included in the file are my test files. I’ll outline the process below so you can see how it works.

The first script is a bash script that prints a file tree into a text file and starts the perl script that does the actual searching.

find . -name \*.php > checkfiles.lst
perl checkfiles.pl

The perl script loops through the file list and checks the beginning and end of the file. Here is the code segment to check for any whitespace before the <?php tag:

for ( $line=0; $line < $rows; $line++ ) {
#print “line $line: ” . $myfile[$line];
if ( $myfile[$line] =~ /^[ 0 ) { print "$fname - check leading whitespace\n"; }
break;
}
}

For both of those segments the current file has already been read into an array. This makes the searching must easier to accomplish. Basically all I am doing is checking each line to see if it contains <?php. If it is not the first line I print out a message to check the beginning of the file.

Checking the trailing whitespace is just the opposite. I start with the last line and walk backwards looking for ?>. Here is the code segment that checks the end of the file:

for ( $line = ($rows-1); $line >= 0 ; $line-- ) {
#print "line $line: " . $myfile[$line];
if ( $myfile[$line] =~ /[?][>]/ ) {
if ( $line < ($rows-1) ) { print “$fname – check trailing whitespace\n”; }
break;
}
}

Hopefully you will never need to run any of these checks, but if you do this should make your life much easier.