@ Dan
This seems to be a host problem and my web server configuration knowledge is limited… but I’ll try.
The issue is on the new server, access to TimThumb script is forbidden, the server is returning response 403. I really don’t know the reason why it would be forbidden, but…
A Google search has turned up these possible solutions:
Try adding this to the .htaccess file:
SecFilterEngine Off
SecFilterScanPost Off
If that doesn’t work, try:
Set the permission on the following folder to 0775:
../wp-content/plugins/connections/includes/timthumb/
The try setting the permissions on this file to 0775:
../wp-content/plugins/connections/includes/timthumb/timthumb.php
If that doesn’t work, you’ll have to contact your web host and ask them to white list the following mod_sec rules: 340151 AND 340153 AND 1234234
If you have to have these rules white listed, then you’ll very likely need to change the permissions back to where they were. And they should be, for reference:
Set the permission on the following folder to 0755:
../wp-content/plugins/connections/includes/timthumb/
The try setting the permissions on this file to 0644:
../wp-content/plugins/connections/includes/timthumb/timthumb.php
Please let me know how this goes.