Max File size - This is the maximum file size you wish to allow attached files of this extension to be. Each attachment that is uploaded is going to consume space on your hosting account. You need to take your storage limits into consideration when deciding what size files to allow. There are also several MySQL and PHP settings that affect the maximum file size that you will be able to upload. Generally you will be able to upload files up to a megabyte. If you need larger files and find yourself not able to post them, you'll need to ask for support via our ticket system or on the support forums.
Maximum Width - The maximum width in pixels that an uploaded image can be. This setting only applies for some image types. By default we include all image types that support this option.
Maximum Height - The maximum height in pixels that an uploaded image can be. This setting only applies for some image types. By default we include all image types that support this option.
Mime Type - The mime type dictates how the browser is supposed to handle the files when the attachment is opened. General mime-type lists are available on the Internet but if you choose to leave this option blank, often your browser will simply prompt you to save the attachment.
Display thumbnail for this type - This option generates a thumbnail, a small image, of uploaded images. The thumbnail will be displayed instead of the fullsize image. The fullsize image can be viewed by clicking on the thumbnail. Thumbnails must also be enabled in vBulletin Options -> Message Attachment Options.
Open this attachment in a new browser window - This option will open the attachment in a new window. Some users prefer to have control over how attachments open.
Enabled - Controls whether or not this attachment type is allowed to be uploaded.
Press when you have finalized your new attachment file type.