MySQL & PHP - multiple users cause error

[asterias]

Hello, I have a mysql database tied to a php application. The problem I am having is that when two users are at the page, it will give me an error: Warning: Supplied argument is not a valid MySQL result resource in /home/mdcmc/bin/include/addform.inc on line 14

The file uploads, but won't add an entry into the database while another person is in the site. I would post the code, but i have it split among many includes, and it would bore you... any ideas?

Thanks!

[Anon]

i think tha the problem is the local area, u can't give 2 sessions in one computer, if u r using IE5 u can cancel the cookies option and in evry entery u shoud open a new page.