The administrator may allow you to use the attachment feature of this forum, which gives you the ability to attach files of certain types to your posts. This could be an image, a text document, a zip file etc. There will be a limit to the file size of any attachments you make, as the forums should not be used as an extension of your hard disk!
To attach a file to a new post, simply click the [Browse] button at the bottom of the post composition page, and locate the file that you want to attach from your local hard drive.
Only certain types of files may be attached: these are the valid file extensions for files to be attached to this forum: bmp gif jpeg jpg png txt.
After posting, the attachment will show up in the body of your message. To view the contents of the attachment (if it is not already displayed) simply click the filename link that appears next to the attachment icon
If you go down to the lower left, you will see what permissions you as a user are allowed. So if it says: You may post attachments, then you can.
But PDF or file extenstion is not an application/file that is supported in the attachments.....but you many be able to copy, paste, and post some information if applied to a txt file in Word.
Look under: Additional Options when you are creating a post, you will see manage attachments........